多項式の記号変数 (Scilabゲートウェイ) 記号変数名を取得する方法.

## 呼び出し手順

入力引数プロファイル:

    SciErr getPolyVariableName(void* _pvCtx, int* _piAddress, char* _pstVarName, int* _piVarNameLen)

## 引数

_pvCtx

  Scilab環境ポインタ, api_scilab.h により定義された "pvApiCtx"で指定.

_piAddress

  変数のアドレス.

_pstVarName

  返される記号変数名

_piVarNameLen

  返される _pstVarNameの長さ

SciErr

  エラー構造体で,エラーメッセージ履歴と最初のエラー番号を格納します.

## 説明

このヘルプは記号変数名を取得する方法を示します.

## ゲートウェイのソース

    #include "api_scilab.h"
    int read_poly(char *fname,void* pvApiCtx)
    {
    	SciErr sciErr;
    	int i,j;
    	//変数の情報
    	int iRows			= 0;
    	int iCols			= 0;
    	int iVarLen			= 0;
    	int* piAddr			= NULL;
    	int* piNbCoef		= NULL;
    	double** pdblReal	= NULL;
    	double** pdblImg	= NULL;
    	char* pstVarname	= NULL;
    	//入力/出力引数を確認
        CheckInputArgument(pvApiCtx, 1, 1);
        CheckOutputArgument(pvApiCtx, 0, 1);
    	sciErr = getVarAddressFromPosition(pvApiCtx, 1, &piAddr);
    	if(sciErr.iErr)
    	{
    		printError(&sciErr, 0);
    		return 0;
    	}
    	if(isVarComplex(pvApiCtx, piAddr) == FALSE)
    	{
    		//Error
    		return 0;
    	}
    	//変数名の長さを取得
    	sciErr = getPolyVariableName(pvApiCtx, piAddr, NULL, &iVarLen);
    	if(sciErr.iErr)
    	{
    		printError(&sciErr, 0);
    		return 0;
    	}
    	//変数名を得るバッファを確保
    	pstVarname = (char*)malloc(sizeof(char) * (iVarLen + 1));//ヌル終端用に1
    	//変数名を取得
    	sciErr = getPolyVariableName(pvApiCtx, piAddr, pstVarname, &iVarLen);
    	if(sciErr.iErr)
    	{
    		printError(&sciErr, 0);
    		return 0;
    	}
    	//最初のコール: 次元を取得
    	sciErr = getComplexMatrixOfPoly(pvApiCtx, piAddr, &iRows, &iCols, NULL, NULL, NULL);
    	if(sciErr.iErr)
    	{
    		printError(&sciErr, 0);
    		return 0;
    	}
    	//係数の配列を確保
    	piNbCoef = (int*)malloc(sizeof(int) * iRows * iCols);
    	//2回目のコール: 係数を取得
    	sciErr = getComplexMatrixOfPoly(pvApiCtx, piAddr, &iRows, &iCols, piNbCoef, NULL, NULL);
    	if(sciErr.iErr)
    	{
    		printError(&sciErr, 0);
    		return 0;
    	}
    	//データ配列を確保
    	pdblReal    = (double**)malloc(sizeof(double*) * iRows * iCols);
    	pdblImg     = (double**)malloc(sizeof(double*) * iRows * iCols);
    	for(i = 0 ; i < iRows * iCols ; i++)
    	{
    		pdblReal[i] = (double*)malloc(sizeof(double) * piNbCoef[i]);
    		pdblImg[i] = (double*)malloc(sizeof(double) * piNbCoef[i]);
    	}
    	//3回目のコール: データを取得
    	sciErr = getComplexMatrixOfPoly(pvApiCtx, piAddr, &iRows, &iCols, piNbCoef, pdblReal, pdblImg);
    	if(sciErr.iErr)
    	{
    		printError(&sciErr, 0);
    		return 0;
    	}
    	//何らかのデータ処理
    	//行列の多項式を反転し 係数を反転
    	for(i = 0 ; i < (iRows * iCols) / 2 ; i++)
    	{
    		int iPos1			= iRows * iCols - 1 - i;
    		double* pdblSave	= NULL;
    		int iNbCoefSave		= 0;
    		//switch array of coefficient
    		pdblSave			= pdblReal[i];
    		pdblReal[i]			= pdblReal[iPos1];
    		pdblReal[iPos1]		= pdblSave;
    		pdblSave			= pdblImg[i];
    		pdblImg[i]			= pdblImg[iPos1];
    		pdblImg[iPos1]		= pdblSave;
    		//switch number of coefficient
    		iNbCoefSave			= piNbCoef[i];
    		piNbCoef[i]			= piNbCoef[iPos1];
    		piNbCoef[iPos1]		= iNbCoefSave;
    	}
    	//係数を切り替え
    	for(i = 0 ; i < iRows * iCols ; i++)
    	{
    		for(j = 0 ; j < piNbCoef[i] /2 ; j++)
    		{
    			int iPos2			= piNbCoef[i] - 1 - j;
    			double dblVal		= pdblReal[i][j];
    			pdblReal[i][j]		= pdblReal[i][iPos2];
    			pdblReal[i][iPos2]	= dblVal;
    			dblVal				= pdblImg[i][j];
    			pdblImg[i][j]		= pdblImg[i][iPos2];
    			pdblImg[i][iPos2]	= dblVal;
    		}
    	}
    	sciErr = createComplexMatrixOfPoly(pvApiCtx, nbInputArgument(pvApiCtx) + 1, pstVarname, iRows, iCols, piNbCoef, pdblReal, pdblImg);
    	if(sciErr.iErr)
    	{
    		printError(&sciErr, 0);
    		return 0;
    	}
    	//OSメモリを解放
    	free(pstVarname);
    	free(piNbCoef);
    	for(i = 0 ; i < iRows * iCols ; i++)
    	{
    		free(pdblReal[i]);
    		free(pdblImg[i]);
    	}
    	free(pdblReal);
    	free(pdblImg);
    	//assign allocated variables to Lhs position
    	AssignOutputVariable(pvApiCtx, 1) = nbInputArgument(pvApiCtx) + 1;
    	return 0;
    }

## Scilabテストスクリプト

    coeff1 = [ ..
    29*%i,22*%i,16*%i,11*%i,7*%i,30,23,17,12,8,-31*%i,-24*%i,-18*%i,-13*%i,-9*%i,32,25,19,14,10,-33*%i,-26*%i,-20*%i,-15*%i,0,34,27,21,0,0,0,-28*%i,0,0,0,36-35*%i,0,0,0,0; ..
    4*%i,2*%i,%i,22,16,5,-3,0,-23*%i,-17*%i,-6*%i,0,0,24,18,0,0,0,-25*%i,-19*%i,0,0,0,26,20,0,0,0,-27*%i,-21*%i,0,0,0,28,0,0,0,0,0,0; ..
    11,7,4,2,1,-12*%i,-8*%i,-5*%i,3*%i,0,13,9,6,0,0,-14*%i,-10*%i,0,0,0,15,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];
    x = poly(0, "x");
    p1  = 1;
    p2  = 2 * x + 3 * %i;
    p3  = 4 * x**2 - 5 * %i * x + 6;
    p4  = 7 * x**3 - 8 * %i * x**2 + 9 * x - 10 * %i;
    p5  = 11 * x**4 - 12 * %i * x**3 + 13 * x**2 - 14 * %i * x + 15;
    p6  = 16 * x**5 - 17 * %i * x**4 + 18 * x**3 - 19 * %i * x**2 + 20 * x  - 21 * %i;
    p7  = 22 * x**6 - 23 * %i * x**5 + 24 * x**4 - 25 * %i * x**3 + 26 * x**2 - 27 * %i * x + 28;
    p8  = %i;
    p9  = 2 * %i * x - 3;
    p10 = 4 * %i * x**2 + 5 * x - 6 * %i;
    p11 = 7 * %i * x**3 + 8 * x**2 - 9 * %i * x + 10;
    p12 = 11 * %i * x**4 + 12 * x**3 - 13 * %i * x**2 + 14 * x - 15 * %i;
    p13 = 16 * %i * x**5 + 17 * x**4 - 18 * %i * x**3 + 19 * x**2 - 20 * %i * x  + 21;
    p14 = 22 * %i * x**6 + 23 * x**5 - 24 * %i * x**4 + 25 * x**3 - 26 * %i * x**2 + 27 * x - 28 * %i;
    p15 = 29 * %i * x**7 + 30 * x**6 - 31 * %i * x**5 + 32 * x**4 - 33 * %i * x**3 + 34 * x**2 - 35 * %i + 36;
    p = [p1, p2, p3, p4, p5 ; p6, p7, p8, p9 ,p10 ; p11, p12, p13, p14, p15];
    p1 = read_poly(p);
    coeff2 = coeff(p1);
    if or(coeff2 <> coeff1) then error("failed"), end