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< a href = "#func-members" > Functions< / a > < / div >
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< div class = "title" > lu_decompose.c File Reference< / div > < / div >
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< p > < a href = "https://en.wikipedia.org/wiki/LU_decompositon" > LU decomposition< / a > of a square matrix
< a href = "#details" > More...< / a > < / p >
< div class = "textblock" > < code > #include < stdio.h> < / code > < br / >
< code > #include < stdlib.h> < / code > < br / >
< code > #include < time.h> < / code > < br / >
< / div > < div class = "textblock" > < div class = "dynheader" >
Include dependency graph for lu_decompose.c:< / div >
< div class = "dyncontent" >
< div class = "center" > < iframe scrolling = "no" frameborder = "0" src = "../../de/d4e/lu__decompose_8c__incl.svg" width = "243" height = "127" > < p > < b > This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.< / b > < / p > < / iframe >
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< tr class = "heading" > < td colspan = "2" > < h2 class = "groupheader" > < a name = "func-members" > < / a >
Functions< / h2 > < / td > < / tr >
< tr class = "memitem:aae40b90a8efd645c749128cf8072bbb4" > < td class = "memItemLeft" align = "right" valign = "top" > int  < / td > < td class = "memItemRight" valign = "bottom" > < a class = "el" href = "../../dc/d2e/lu__decompose_8c.html#aae40b90a8efd645c749128cf8072bbb4" > lu_decomposition< / a > (double **A, double **< a class = "el" href = "../../df/db3/struct_l.html" > L< / a > , double **U, int mat_size)< / td > < / tr >
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< tr class = "memdesc:aae40b90a8efd645c749128cf8072bbb4" > < td class = "mdescLeft" >   < / td > < td class = "mdescRight" > Perform LU decomposition on matrix. < a href = "../../dc/d2e/lu__decompose_8c.html#aae40b90a8efd645c749128cf8072bbb4" > More...< / a > < br / > < / td > < / tr >
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void  < / td > < td class = "memItemRight" valign = "bottom" > < a class = "el" href = "../../dc/d2e/lu__decompose_8c.html#a0789beb8d3396582d77b7aedf5e5554a" > display< / a > (double **A, int N)< / td > < / tr >
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< tr class = "memdesc:a0789beb8d3396582d77b7aedf5e5554a" > < td class = "mdescLeft" >   < / td > < td class = "mdescRight" > Function to display square matrix. < br / > < / td > < / tr >
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< tr class = "memdesc:a3c04138a5bfe5d72780bb7e82a18e627" > < td class = "mdescLeft" >   < / td > < td class = "mdescRight" > Main function. < br / > < / td > < / tr >
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< tr class = "separator:a3c04138a5bfe5d72780bb7e82a18e627" > < td class = "memSeparator" colspan = "2" >   < / td > < / tr >
< / table >
< a name = "details" id = "details" > < / a > < h2 class = "groupheader" > Detailed Description< / h2 >
< div class = "textblock" > < p > < a href = "https://en.wikipedia.org/wiki/LU_decompositon" > LU decomposition< / a > of a square matrix < / p >
< dl class = "section author" > < dt > Author< / dt > < dd > < a href = "https://github.com/kvedala" > Krishna Vedala< / a > < / dd > < / dl >
< / div > < h2 class = "groupheader" > Function Documentation< / h2 >
< a id = "aae40b90a8efd645c749128cf8072bbb4" > < / a >
< h2 class = "memtitle" > < span class = "permalink" > < a href = "#aae40b90a8efd645c749128cf8072bbb4" > ◆ < / a > < / span > lu_decomposition()< / h2 >
< div class = "memitem" >
< div class = "memproto" >
< table class = "memname" >
< tr >
< td class = "memname" > int lu_decomposition < / td >
< td > (< / td >
< td class = "paramtype" > double **  < / td >
< td class = "paramname" > < em > A< / em > , < / td >
< / tr >
< tr >
< td class = "paramkey" > < / td >
< td > < / td >
< td class = "paramtype" > double **  < / td >
< td class = "paramname" > < em > L< / em > , < / td >
< / tr >
< tr >
< td class = "paramkey" > < / td >
< td > < / td >
< td class = "paramtype" > double **  < / td >
< td class = "paramname" > < em > U< / em > , < / td >
< / tr >
< tr >
< td class = "paramkey" > < / td >
< td > < / td >
< td class = "paramtype" > int  < / td >
< td class = "paramname" > < em > mat_size< / em >   < / td >
< / tr >
< tr >
< td > < / td >
< td > )< / td >
< td > < / td > < td > < / td >
< / tr >
< / table >
< / div > < div class = "memdoc" >
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< p > Perform LU decomposition on matrix. < / p >
< dl class = "params" > < dt > Parameters< / dt > < dd >
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< table class = "params" >
< tr > < td class = "paramdir" > [in]< / td > < td class = "paramname" > A< / td > < td > matrix to decompose < / td > < / tr >
< tr > < td class = "paramdir" > [out]< / td > < td class = "paramname" > < a class = "el" href = "../../df/db3/struct_l.html" > L< / a > < / td > < td > output < a class = "el" href = "../../df/db3/struct_l.html" > L< / a > matrix < / td > < / tr >
< tr > < td class = "paramdir" > [out]< / td > < td class = "paramname" > U< / td > < td > output U matrix < / td > < / tr >
< tr > < td class = "paramdir" > [in]< / td > < td class = "paramname" > mat_size< / td > < td > input square matrix size < / td > < / tr >
< / table >
< / dd >
< / dl >
< div class = "fragment" > < div class = "line" > < a name = "l00021" > < / a > < span class = "lineno" > 21< / span >   {< / div >
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< div class = "line" > < a name = "l00024" > < / a > < span class = "lineno" > 24< / span >   < span class = "comment" > // regularize each row< / span > < / div >
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< div class = "line" > < a name = "l00033" > < / a > < span class = "lineno" > 33< / span >   < span class = "comment" > // Summation of L[i,j] * U[j,k]< / span > < / div >
< div class = "line" > < a name = "l00034" > < / a > < span class = "lineno" > 34< / span >   < span class = "keywordtype" > double< / span > lu_sum = 0.;< / div >
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< div class = "line" > < a name = "l00035" > < / a > < span class = "lineno" > 35< / span >   < span class = "keywordflow" > for< / span > (j = 0; j < row; j++) lu_sum += < a class = "code" href = "../../df/db3/struct_l.html" > L< / a > [row][j] * U[j][col];< / div >
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< div class = "line" > < a name = "l00037" > < / a > < span class = "lineno" > 37< / span >   < span class = "comment" > // Evaluate U[i,k]< / span > < / div >
< div class = "line" > < a name = "l00038" > < / a > < span class = "lineno" > 38< / span >   U[row][col] = A[row][col] - lu_sum;< / div >
< div class = "line" > < a name = "l00039" > < / a > < span class = "lineno" > 39< / span >   }< / div >
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< div class = "line" > < a name = "l00053" > < / a > < span class = "lineno" > 53< / span >   < span class = "comment" > // Summation of L[i,j] * U[j,k]< / span > < / div >
< div class = "line" > < a name = "l00054" > < / a > < span class = "lineno" > 54< / span >   < span class = "keywordtype" > double< / span > lu_sum = 0.;< / div >
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< div class = "line" > < a name = "l00056" > < / a > < span class = "lineno" > 56< / span >   < / div >
< div class = "line" > < a name = "l00057" > < / a > < span class = "lineno" > 57< / span >   < span class = "comment" > // Evaluate U[i,k]< / span > < / div >
< div class = "line" > < a name = "l00058" > < / a > < span class = "lineno" > 58< / span >   < a class = "code" href = "../../df/db3/struct_l.html" > L< / a > [col][row] = (A[col][row] - lu_sum) / U[row][row];< / div >
< div class = "line" > < a name = "l00059" > < / a > < span class = "lineno" > 59< / span >   }< / div >
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