diff --git a/amscppperm1.code-workspace b/amscppperm1.code-workspace
index 057f439..911b10b 100644
--- a/amscppperm1.code-workspace
+++ b/amscppperm1.code-workspace
@@ -3,14 +3,8 @@
 		{
 			"path": "."
 		},
-		{
-			"path": "../../sourceprojs23/camsimglib3"
-		},
 		{
 			"path": "../../sourceprojs23/amsmathutil2"
-		},
-		{
-			"path": "../../sourceprojs23/amscppfilesys3"
 		}
 	]
-}
\ No newline at end of file
+}
diff --git a/build/__pycache__/amsbuildlib4.cpython-39.pyc b/build/__pycache__/amsbuildlib4.cpython-39.pyc
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index 0000000..c6e3e00
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index 0000000..4d3ff0d
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diff --git a/build_msvc64/objstore/permutation.obj b/build_msvc64/objstore/permutation.obj
new file mode 100644
index 0000000..2e24606
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diff --git a/build_msvc64/objstore/permutation_basic.obj b/build_msvc64/objstore/permutation_basic.obj
new file mode 100644
index 0000000..1ebb30d
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diff --git a/include/amscppperm1/amscppperm1.hpp b/include/amscppperm1/amscppperm1.hpp
index eff8a01..0015203 100644
--- a/include/amscppperm1/amscppperm1.hpp
+++ b/include/amscppperm1/amscppperm1.hpp
@@ -4,6 +4,61 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <math.h>
+#include <new>
+
+extern "C"
+{
+
+////////////////////////////////////////////
+//Basic operations on preallocated buffers//
+//for C library export                    //
+////////////////////////////////////////////
+
+static const int amsperm1_success = 0;
+static const int amsperm1_failure = -1;
+
+//basic factorial found with integer loop
+int amsperm1_factorial(int n);
+
+//Is the multi-index in the appropriate factoriadic range?
+// position 0 can range from [0 to length)
+// position 1 can range from [0 to (length-1))
+//parameters:
+//  int mindex[length] - multi-index input
+//  int length - multi-index length output
+bool amsperm1_mindex_valid(int *mindex, int length);
+
+
+bool amsperm1_perm_valid(int *perm, int *wrk, int length);
+
+//returns a factoriadic multi-index for a given index.
+//Each factoriadic multi-index corresponds to a permutation according to a simple algorithm
+// factoriadic indices range from (ex 4 length case) {0,0,0,0} to {3,2,1,0}
+// parameters:
+//  index - [0 to factorial(length)) index of permutation
+//  mindex - factoriadic multi-index output (size=length)
+//  length - length of the permutation (number of elements to permute)
+// return value:
+//  0: success
+//  -1 : privided index was out of the valid range 
+int amsperm1_index_to_mindex(int index, int *mindex, int length);
+
+int amsperm1_mindex_to_index(int *mindex, int length);
+
+
+int amsperm1_mindex_to_perm(int *mindex, int *perm, int *wrk, int length);
+
+
+int amsperm1_perm_to_mindex(int *perm, int *mindex, int *wrk, int length);
+
+int amsperm1_index_to_perm(int index, int *perm, int *mindex, int *wrk, int length);
+
+int amsperm1_perm_to_index(int *perm, int *mindex, int *wrk, int length);
+
+void amsperm1_test_basicperm1();
+
+}; //end extern C
+
 
 
 namespace ams
@@ -11,42 +66,83 @@ namespace ams
 namespace perm
 {
 
-//Basic operations on preallocated buffers
-//for later C library export
 
 static const int perm_success = 0;
 static const int perm_failure = -1;
 
 int factorial(int n);
 
-int index_to_mindex(int index, int *mindex, int ndim);
+//Iteratable Permutation Class
+//Provides an object for iterating over permutations of low dimension
+//These can be stepped along 
+class ipermutation
+{
+public:
+    int length;
+    int *perm; //permutation
+
+    int index; //do I want these also stored with the permutation variable?
+    int *mind; //factoriadic multi-index
+    int *wrk; //working memory buffer
+
+    ipermutation();
+    ipermutation(const int _length);
+    ipermutation(const int _index, const int _length);
+    ipermutation(const int *parray, const int _length);
+    ~ipermutation();
+
+    ipermutation(const ipermutation& other);
+
+    int resize(const int _nlength);
 
-int mindex_to_index(int *mindex, int ndim);
-int mindex_to_perm(int *mindex, int *perm, int *wrk, int ndim);
-int perm_to_mindex(int *perm, int *mindex, int *wrk, int ndim);
+    ipermutation operator=(const ipermutation &other);
+    int& operator[](const int ind);
+    const int& operator[](const int ind) const;
 
-bool perm_valid(int *perm, int ndim);
+    bool valid() const;
+    bool operator==(const ipermutation other) const;
 
-bool mindex_valid(int *mindex, int ndim);
+    //pre-increment operator
+    ipermutation& operator++();
+    ipermutation& operator--();
 
-void index_to_perm(int index, int *perm, int ndim);
-int perm_to_index(int *perm, int ndim);
+    //post-increment operators
+    ipermutation operator++(int);
+    ipermutation operator--(int);
 
+    ipermutation operator*(const ipermutation b) const; //compose permutations
+    ipermutation inverse() const; //invert permutation
 
+    //returns first and last permutations of a given lengthension
+    static ipermutation first(int _nlength);
+    static ipermutation last(int _nlength);
 
+    int levi_civita() const;
 
-//Permutation class
+    void print(int style=0);
+
+};
+
+ipermutation ipermutation_first(int _nlength);
+ipermutation ipermutation_last(int _nlength);
+int levi_civita(const ipermutation p);
+
+void test_ipermutation1();
+
+// non-indexable permutation class
+// the same permutation logic, but for larger permutation sets
+// can't index, can't increment or decrement a sequence, but can still
+// compose, test validity, test levi_civita sign, apply to arrays, etc.
 class permutation
 {
-public:
-    int dim;
+    public:
+    int length;
     int *data;
-
-    permutation();
-    permutation(int _dim);
-    ~permutation();
+    
+    
 };
 
+
 }; //end namespace perm
 }; //end namespace ams
 
diff --git a/src/amscppperm1/permutation.cpp b/src/amscppperm1/permutation.cpp
index f23d40d..5970497 100644
--- a/src/amscppperm1/permutation.cpp
+++ b/src/amscppperm1/permutation.cpp
@@ -5,21 +5,445 @@ namespace ams
 namespace perm
 {
 
-    permutation::permutation()
+    ipermutation::ipermutation()
     {
-        dim = 0;
-        data = NULL;
+        length = 0;
+        perm = NULL;
+        index = -1;
+        mind = NULL;
+        wrk = NULL;
+
+        return;
+    }
+
+    ipermutation::~ipermutation()
+    {
+        if(perm!=NULL) {delete[] perm; perm = NULL;}
+        if(mind!=NULL) {delete[] mind; mind = NULL;}
+        if(wrk!=NULL) {delete[] wrk; wrk = NULL;}
+        length = 0;
+        index = -1;
+
+        return;
+    }
+
+    ipermutation::ipermutation(const int _length)
+    {
+        length = 0;
+        perm = NULL;
+        index = -1;
+        mind = NULL;
+        wrk = NULL;
+
+        this->resize(_length);
+    }
+
+    ipermutation::ipermutation(const int _index, const int _length)
+    {
+        int res = perm_failure;
+        length = 0;
+        perm = NULL;
+        index = -1;
+        mind = NULL;
+        wrk = NULL;
+
+        if(_length>0)
+        {
+            res = this->resize(_length);
+            if(res==perm_success)
+            {
+                index = _index;
+                amsperm1_index_to_mindex(index,mind,length);
+                amsperm1_mindex_to_perm(mind,perm,wrk,length);
+            }
+        }  
+    }
+
+    ipermutation::ipermutation(const int *parray, const int _length)
+    {
+        int I;
+        int res = perm_failure;
+        length = 0;
+        perm = NULL;
+        index = -1;
+        mind = NULL;
+        wrk = NULL;
+
+        if(_length>0)
+        {
+            res = this->resize(_length);
+            if(res==perm_success)
+            {
+                for(I=0;I<length;I++) perm[I] = parray[I];
+                amsperm1_perm_to_mindex(perm,mind,wrk,length);
+                index = amsperm1_mindex_to_index(mind,length);
+            }
+        }  
+        return;
+    }
+
+    int ipermutation::resize(const int _nlength)
+    {
+        int ret = perm_success;
+
+        int *newperm = NULL;
+        int *newmind = NULL;
+        int *newwrk = NULL;
+        int newind;
+
+        int I;
+
+        if(_nlength<=0)
+        {
+            length = 0;
+            index = -1;
+            if(perm!=NULL) {delete[] perm; perm=NULL;}
+            if(mind!=NULL) {delete[] mind; mind=NULL;}
+            if(wrk!=NULL) {delete[] wrk; wrk=NULL;}
+            
+            return ret;
+        }
+
+        newperm = new(std::nothrow) int[_nlength];
+        newmind = new(std::nothrow) int[_nlength];
+        newwrk = new(std::nothrow) int[_nlength];
+        
+        if(newperm==NULL || newmind == NULL || newwrk == NULL)
+        {
+            if(newperm!=NULL) {delete[] newperm; newperm=NULL;}
+            if(newmind!=NULL) {delete[] newmind; newmind=NULL;}
+            if(newwrk!=NULL) {delete[] newwrk; newwrk=NULL;}
+
+            ret = perm_failure;
+            return ret;
+        }
+
+        for(I=0;I<length && I<_nlength; I++)
+        {
+            newmind[I] = mind[I];
+        }
+        for(I=length;I<_nlength;I++) newmind[I] = 0;
+
+        newind = amsperm1_mindex_to_index(newmind,_nlength);
+        amsperm1_mindex_to_perm(newmind,newperm,newwrk,_nlength);
+
+        if(perm!=NULL) {delete[] perm; perm = NULL;}
+        if(mind!=NULL) {delete[] mind; mind = NULL;}
+        if(wrk!=NULL) {delete[] wrk; wrk = NULL;}
+        length = 0;
+        index = -1;
+
+        length = _nlength;
+        index = newind;
+        perm = newperm;
+        mind = newmind;
+        wrk = newwrk;
+
+
+        return ret;
+    }
+
+    ipermutation::ipermutation(const ipermutation& other)
+    {
+        int res;
+        length = 0;
+        perm = NULL;
+        index = -1;
+        mind = NULL;
+        wrk = NULL;
+
+        int I;
+
+        if(this!=&other)
+        {
+            res = this->resize(other.length);
+            if(res==perm_success)
+            {
+               for(I=0;I<length;I++)
+               {
+                this->perm[I] = other.perm[I];
+                this->wrk[I] = other.wrk[I];
+                this->mind[I] = other.mind[I];
+                this->index = other.index;
+               }  
+            }
+        }
+    }
+
+    ipermutation ipermutation::operator=(const ipermutation &other)
+    {
+        int res;
+        int I;
+        if(this!=&other)
+        {
+            res = this->resize(other.length);
+            if(res==perm_success)
+            {
+               for(I=0;I<length;I++)
+               {
+                this->perm[I] = other.perm[I];
+                this->wrk[I] = other.wrk[I];
+                this->mind[I] = other.mind[I];
+                this->index = other.index;
+               }  
+            }
+        }
+
+        return *this;
+    }
+
+    int& ipermutation::operator[](const int ind)
+    {
+        return perm[ind];
+    }
+
+    const int& ipermutation::operator[](const int ind) const
+    {
+        return perm[ind];
+    }
+
+    int factorial(int n)
+    {
+        return amsperm1_factorial(n);
+    }
+
+    bool ipermutation::valid() const
+    {
+        bool ret = 1;
+        int *lmind = NULL;
+        int *lwrk = NULL;
+        int *lperm = NULL;
+
+        if(index<0 || index>=factorial(length))
+        {
+            ret = 0; return ret;
+        }
+
+        //other tests - skip for speed?
+
+        return ret;
+    }
+
+    bool ipermutation::operator==(const ipermutation other) const
+    {
+        bool ret = 1;
+        int I;
+        
+        if(length!=other.length)
+        {
+            ret = 0; return ret;
+        }
+        if(index != other.index)
+        {
+            ret = 0; return ret;
+        }
+
+        //additional tests (skip for speed?)
+        for(I=0;I<length && I<other.length;I++)
+        {
+            if(perm[I]!=other.perm[I]) {ret = 0; break;}
+            if(mind[I]!=other.mind[I]) {ret = 0; break;}
+        }
+
+        return ret;
+    }
+
+    ipermutation ipermutation_first(int _nlength)
+    {
+        ipermutation ret = ipermutation(0,_nlength);
+        return ret;
+    }
+
+    ipermutation ipermutation_last(int _nlength)
+    {
+        int f = factorial(_nlength);
+        ipermutation ret = ipermutation(f-1,_nlength);
+        return ret;
+    }
+
+    int levi_civita(const ipermutation p)
+    {
+        int ret = 0;
+        bool v = p.valid();
+        if(v)
+        {
+            ret = 2*(!(p.index%2))-1;
+        }
+        return ret;
+    }
+
+    //pre-increment operator
+    ipermutation& ipermutation::operator++()
+    {
+        int I;
+        if(valid())
+        {
+            if(index+1>=0 && index+1<factorial(length))
+            {
+                index = index + 1;
+                amsperm1_index_to_mindex(index,mind,length);
+                amsperm1_mindex_to_perm(mind,perm,wrk,length);
+            } 
+            else
+            {
+                index = -1;
+                for(I=0;I<length;I++)
+                {
+                    perm[I] = -1;
+                    mind[I] = -1;
+                    wrk[I] = 0;
+                }
+            }
+        }
+        return *this;
+    }
+
+    ipermutation& ipermutation::operator--()
+    {
+        int I;
+        if(valid())
+        {
+            if(index-1>=0 && index-1<factorial(length))
+            {
+                index = index - 1;
+                amsperm1_index_to_mindex(index,mind,length);
+                amsperm1_mindex_to_perm(mind,perm,wrk,length);
+            } 
+            else
+            {
+                index = -1;
+                for(I=0;I<length;I++)
+                {
+                    perm[I] = -1;
+                    mind[I] = -1;
+                    wrk[I] = 0;
+                }
+            }
+        }
+        return *this;
+    }
+
+    //post-increment operators
+    ipermutation ipermutation::operator++(int)
+    {
+        ipermutation ret = *this;
+        //++ret;
+        this->operator++();
+        return ret;
+    }
+
+    ipermutation ipermutation::operator--(int)
+    {
+        ipermutation ret = *this;
+        //--ret;
+        this->operator--();
+        return ret;
+    }
+
+    void ipermutation::print(int style)
+    {
+        int I;
+        if(style==0)
+        {
+            printf("{");
+            for(I=0;I<length-1;I++) printf("%d,",perm[I]);
+            printf("%d}",perm[length-1]);
+        }
+        else if(style==1)
+        {
+            printf("%d:{",index);
+            for(I=0;I<length-1;I++) printf("%d,",perm[I]);
+            printf("%d}",perm[length-1]);
+        }
+        else if(style==2)
+        {
+            printf("ipermutation[%d]:{",index);
+            for(I=0;I<length-1;I++) printf("%d,",perm[I]);
+            printf("%d}",perm[length-1]);
+        }
         return;
     }
 
-    permutation::~permutation()
+    void test_ipermutation1()
     {
-        if(data!=NULL) {delete[] data; data = NULL;}
-        dim = 0;
+        ipermutation a = ipermutation(4);
+        ipermutation *b = NULL;
+
+        b = new(std::nothrow) ipermutation(4);
+
+        a.print(); printf("\n");
+        b->print(); printf("\n");
+        a++;
+        a.print(); printf("\n");
+        ++a; a.print(); printf("\n");
+        a++;
+        a++;
+        a++;
+        *b = a;
+        b->print(2); printf("\n");
+        b->resize(3);
+        a.resize(5);
+        a.print(); printf("\n");
+        b->print(); printf("\n");
+        int I;
+        *b = ipermutation_first(3);
+        for(I=0;I<8;I++)
+        {
+            
+            b->print(2); printf("\n");
+            (*b)++;
+        }
+
+        for(a=ipermutation_last(3);a.valid();a--)
+        {
+            a.print(2); printf("\n");
+        }
+
+        delete(b);
 
         return;
     }
 
+    //compose permutations
+    ipermutation ipermutation::operator*(const ipermutation b) const
+    {
+        ipermutation ret = ipermutation(this->length);
+
+        return ret;
+    }
+    
+    //invert permutation
+    ipermutation ipermutation::inverse() const
+    {
+        ipermutation ret = ipermutation(this->length);
+
+        return ret;
+    } 
+
+    //returns first and last permutations of a given lengthension
+    ipermutation ipermutation::first(int _nlength)
+    {
+        ipermutation ret = ipermutation(0,_nlength);
+        return ret;
+    }
+
+    ipermutation ipermutation::last(int _nlength)
+    {
+        int f = factorial(_nlength);
+        ipermutation ret = ipermutation(f-1,_nlength);
+        return ret;
+    }
+
+    int ipermutation::levi_civita() const
+    {
+        int ret = 0;
+        if(valid())
+        {
+            ret = 2*(!(index%2))-1;
+        }
+        return ret;
+    }
+
 
 }; //end namespace perm
 }; //end namespace ams
\ No newline at end of file
diff --git a/src/amscppperm1/permutation_basic.cpp b/src/amscppperm1/permutation_basic.cpp
index e18aa3a..ad04a48 100644
--- a/src/amscppperm1/permutation_basic.cpp
+++ b/src/amscppperm1/permutation_basic.cpp
@@ -1,16 +1,14 @@
 #include <amscppperm1/amscppperm1.hpp>
 
-namespace ams
-{
-namespace perm
+extern "C"
 {
 
     //basic factorial found with integer loop
-    int factorial(int n)
+    int amsperm1_factorial(int n)
     {
         int I;
         int ret = 0;
-        if(n>=0)
+        if(n>=0 && n<=12)
         {
             ret = 1;
             for(I=0;I<n;I++)
@@ -18,29 +16,33 @@ namespace perm
                 ret = ret*(I+1);
             }
         }
+        if(n>12)
+        {
+            ret = -1; //overflow error
+        }
         return ret;
     }
 
     //returns a factoriadic multi-index for a given index.
     //Each factoriadic multi-index corresponds to a permutation according to a simple algorithm
-    // factoriadic indices range from (ex 4 dim case) {0,0,0,0} to {3,2,1,0}
+    // factoriadic indices range from (ex 4 length case) {0,0,0,0} to {3,2,1,0}
     // parameters:
-    //  index - [0 to factorial(ndim)) index of permutation
-    //  mindex - factoriadic multi-index output (size=ndim)
-    //  ndim - dimension of the permutation (number of elements to permute)
+    //  index - [0 to factorial(length)) index of permutation
+    //  mindex - factoriadic multi-index output (size=length)
+    //  length - length of the permutation (number of elements to permute)
     // return value:
     //  0: success
     //  -1 : privided index was out of the valid range 
-    int index_to_mindex(int index, int *mindex, int ndim)
+    int amsperm1_index_to_mindex(int index, int *mindex, int length)
     {
-        int ret = -1;
+        int ret = amsperm1_failure;
         int I,J,K;
-        if(index>=0 && index<factorial(ndim))
+        if(index>=0 && index<amsperm1_factorial(length))
         {
-            ret = 0; //success
-            K = ndim;
+            ret = amsperm1_success; //success
+            K = length;
             J = index;
-            for(I=0;I<ndim;I++)
+            for(I=0;I<length;I++)
             {
                 mindex[I] = J%K;
                 J = (J - mindex[I])/K;
@@ -49,9 +51,9 @@ namespace perm
         }
         else
         {
-            ret = -1; //error
+            ret = amsperm1_failure; //error
             //invalid index
-            for(I=0;I<ndim;I++)
+            for(I=0;I<length;I++)
                 mindex[I] = -1;
         }
 
@@ -60,15 +62,18 @@ namespace perm
     }
 
     //Is the multi-index in the appropriate factoriadic range?
-    // position 0 can range from [0 to ndim)
-    // position 1 can range from [0 to (ndim-1))
-    bool mindex_valid(int *mindex, int ndim)
+    // position 0 can range from [0 to length)
+    // position 1 can range from [0 to (length-1))
+    //parameters:
+    //  int mindex[length] - multi-index input
+    //  int length - multi-index length output
+    bool amsperm1_mindex_valid(int *mindex, int length)
     {
         int I;
         bool ret = 1;
-        for(I=0;I<ndim;I++)
+        for(I=0;I<length;I++)
         {
-            if(mindex[I]<0 || mindex[I]>=(ndim-I))
+            if(mindex[I]<0 || mindex[I]>=(length-I))
             {
                 ret = 0;
                 break;
@@ -77,19 +82,19 @@ namespace perm
         return ret;
     }
 
-    int mindex_to_index(int *mindex, int ndim)
+    int amsperm1_mindex_to_index(int *mindex, int length)
     {
         int ret = -1;
         int I;
         int K;
-        if(mindex_valid(mindex,ndim))
+        if(amsperm1_mindex_valid(mindex,length))
         {
             K = 1;
             ret = 0;
-            for(I=0;I<ndim;I++)
+            for(I=0;I<length;I++)
             {
                 ret = ret + mindex[I]*K;
-                K = K*(ndim-I);
+                K = K*(length-I);
             }
         }
         else
@@ -101,20 +106,198 @@ namespace perm
         return ret;
     }
 
-    int mindex_to_perm(int *mindex, int *perm, int *wrk, int ndim)
+    //multi-index to permutation
+    //parameters:
+    //  mindex[length] - input factoriadic multi-index
+    //  perm[length] - output permutation
+    //  wrk[length] - working memory buffer
+    //  length - length of permutation
+    //return values:
+    //  amsperm1_success - result should be a valid permutation
+    //  amsperm1_failure - invalid multi-index supplied
+    int amsperm1_mindex_to_perm(int *mindex, int *perm, int *wrk, int length)
     {
-        int ret = -1;
+        int I,J,K,L;
+        int ret = amsperm1_failure;
+        if(!amsperm1_mindex_valid(mindex,length))
+        {
+            ret = amsperm1_failure;
+            for(I=0;I<length;I++) perm[I] = -1;
+            return ret;
+        }
+        else
+        {
+            for(I=0;I<length;I++) wrk[I] = 0;
+            for(I=0;I<length;I++)
+            {
+                J = mindex[I];
+                L = 0;
+                for(K=0;K<length;K++)
+                {
+                    if(wrk[K]==0)
+                    {
+                        L = L + 1;
+                        if(L==(J+1))
+                        {
+                            perm[I] = K;
+                            wrk[K] = 1;
+                            break;
+                        }
+                    }
+                }
+            }
+            ret = amsperm1_success;
+        }
 
         return ret;
     }
     
-    int perm_to_mindex(int *perm, int *mindex, int *wrk, int ndim)
+    //check validity of permutation
+    //parameters:
+    //int perm[length] - input permutation
+    //int wrk[length] - working buffer
+    //int length - permutation array length
+    //return values:
+    //  1 - is a valid permutation
+    //  0 - is not a valid permutation
+    bool amsperm1_perm_valid(int *perm, int *wrk, int length)
     {
-        int ret = -1;
+        bool ret = 1;
+        int I;
+        for(I=0;I<length;I++) wrk[I] = 0;
+        for(I=0;I<length;I++)
+        {
+            if(perm[I]<0 || perm[I]>=length)
+            {
+                ret = 0;
+                break;
+            }
+            if(wrk[perm[I]]==1)
+            {
+                ret = 0;
+                break;
+            }
+            else
+            {
+                wrk[perm[I]]=1;
+            }
+        }
+
+        return ret;
+    }
+
+    int amsperm1_perm_to_mindex(int *perm, int *mindex, int *wrk, int length)
+    {
+        int ret = amsperm1_failure;
+        int I,J,K,L;
+
+        if(!amsperm1_perm_valid(perm,wrk,length))
+        {
+            for(I=0;I<length;I++) mindex[I] = -1;
+            ret = amsperm1_failure;
+            return ret;
+        }
+
+        for(I=0;I<length;I++) wrk[I]=0;
+        for(I=0;I<length;I++)
+        {
+            J = perm[I];
+            L = 0;
+            for(K=0;K<=J;K++)
+            {
+                if(wrk[K]==0)
+                {
+                    L = L + 1;
+                }
+            }
+            wrk[J] = 1;
+            mindex[I] = L-1;
+        }
+        ret = amsperm1_success;
+
         
         return ret;
     }
 
+    int amsperm1_index_to_perm(int index, int *perm, int *mindex, int *wrk, int length)
+    {
+        int ret = amsperm1_failure;
+
+        if(index<0 || index>=amsperm1_factorial(length))
+        {
+            return ret;
+        }
+        amsperm1_index_to_mindex(index,mindex,length);
+        amsperm1_mindex_to_perm(mindex,perm,wrk,length);
+        ret = amsperm1_success;
+        return ret;
+    }
+
+    int amsperm1_perm_to_index(int *perm, int *mindex, int *wrk, int length)
+    {
+        int ret = -1;
+        if(!amsperm1_perm_valid(perm,wrk,length))
+        {
+            return ret;
+        }
+
+        amsperm1_perm_to_mindex(perm,mindex,wrk,length);
+        ret = amsperm1_mindex_to_index(mindex,length);
+
+        return ret;
+    }
+
+    static void _intl_print_array(int *array, int length)
+    {
+        int I;
+        printf("{");
+        for(I=0;I<length-1;I++)
+        {
+            printf("%d,",array[I]);
+        }
+        printf("%d}",array[length-1]);
+        return;
+    }
+
+    void amsperm1_test_basicperm1()
+    {
+        int I,J;
+        int length = 4;
+        int *perm1 = NULL;
+        int *perm2 = NULL;
+        int *mind1 = NULL;
+        int *mind2 = NULL;
+        int *wrk = NULL;
+
+
+        perm1 = new(std::nothrow) int[length];
+        perm2 = new(std::nothrow) int[length];
+        mind1 = new(std::nothrow) int[length];
+        mind2 = new(std::nothrow) int[length];
+        wrk = new(std::nothrow) int[length];
+        
+        printf("Tests of basic permutation and multi-index operations..\n");
+        for(I=-1;I<amsperm1_factorial(length)+1;I++)
+        {
+            amsperm1_index_to_mindex(I,mind1,length);
+            J = amsperm1_mindex_to_index(mind1,length);
+            amsperm1_mindex_to_perm(mind1,perm1,wrk,length);
+            amsperm1_perm_to_mindex(perm1,mind2,wrk,length);
+            printf("%d\t",I); 
+            _intl_print_array(mind1,length); printf("\t"); 
+            _intl_print_array(perm1,length); printf("\t");
+            _intl_print_array(mind2,length); printf("\t");
+            printf("%d\n",J);
+        }
+
+
+        delete[] perm1;
+        delete[] perm2;
+        delete[] mind1;
+        delete[] mind2;
+        delete[] wrk;
+
+        return;
+    }
 
-}; //end namespace perm
-}; //end namespace ams
\ No newline at end of file
+}; //end extern "C"
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index 48f6db0..2f63c79 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3,7 +3,8 @@
 int main(int argc, char* argv[])
 {
     int ret = 0;
-    printf("ams c++ project template tests.\n");
-
+    printf("ams c++ permutation library tests.\n");
+    //amsperm1_test_basicperm1();
+    //ams::perm::test_ipermutation1();
     return ret;
 }
\ No newline at end of file