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Diffstat (limited to 'muse2/muse/widgets/mmath.cpp')
| -rw-r--r-- | muse2/muse/widgets/mmath.cpp | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/muse2/muse/widgets/mmath.cpp b/muse2/muse/widgets/mmath.cpp new file mode 100644 index 00000000..acc8e25a --- /dev/null +++ b/muse2/muse/widgets/mmath.cpp @@ -0,0 +1,300 @@ +#include <cmath> +#include "mmath.h" + +// QwtMath - a set of mathematical routines +// +// qwtGetMin -- Find the smallest value in an array +// qwtGetMax -- Find the largest value in an array +// qwtTwistArray -- invert the order of an array +// qwtFloor125 -- Find the largest value fitting in a 1-2-5 pattern +// qwtCeil125 -- Find the smallest value fitting in a 1-2-5 pattern +// qwtChkMono -- Check for monotony +// qwtLinSpace -- construct an array of equally spaced values +// qwtLogSpace -- construct an array of logarithmically equally spaced values +// qwtMax -- Return the largest of two values +// qwtMin -- Return the smallest of two values +// qwtAbs -- return the absolute value +// qwtSign -- Return the sign of a number +// qwtSqr -- Return the square of a number +// qwtCopyArray -- Copy an array into another +// qwtShiftArray -- Shift an array +// qwtSwap -- Swap two values +// qwtSort (1) -- Sort two values +// qwtSort (2) -- Sort two values +// qwtInt -- Return nearest integer +// qwtLim -- Limit a values + + +//------------------------------------------------------------ +//.F qwtGetMin +// Find the smallest value in an array +// +//.u Syntax +//.f double qwtGetMin(double *array, int size) +// +//.u Parameters +//.p double *array, int size +// +//------------------------------------------------------------ + +double qwtGetMin(double *array, int size) +{ + double rv; + int i; + + if (size > 0) + { + rv = array[0]; + for (i=1; i< size; i++) + rv = qwtMin(rv, array[i]); + return rv; + } + else + return 0.0; + +} + + +//------------------------------------------------------------ +// +//.F qwtGetMax +// Find the largest value in an array +// +//.u Syntax +//.f double qwtGetMax(double *array, int size) +// +//.u Parameters +//.p double *array, int size +// +//------------------------------------------------------------ +double qwtGetMax(double *array, int size) +{ + double rv; + int i; + + if (size > 0) + { + rv = array[0]; + for (i=1; i< size; i++) + rv = qwtMax(rv, array[i]); + return rv; + } + else + return 0.0; + +} + + +//------------------------------------------------------------ +// +//.F qwtCeil125 +// Find the smallest value out of {1,2,5}*10^n with an integer number n +// which is greater than or equal to x +// +//.u Syntax +//.f double qwtCeil125(double x) +// +//.u Parameters +//.p double x +// +//------------------------------------------------------------ +double qwtCeil125( double x) +{ + double lx, rv; + double p10, fr; + double sign = ( x > 0) ? 1.0 : -1.0; + + if (x == 0.0) return 0.0; + + lx = log10(fabs(x)); + p10 = floor(lx); + fr = pow(10.0,lx - p10); + if (fr <=1.0) + fr = 1.0; + else if (fr <= 2.0) + fr = 2.0; + else if (fr <= 5.0) + fr = 5.0; + else + fr = 10.0; + rv = fr * pow(10.0,p10); + return sign * rv; +} + + +//------------------------------------------------------------ +// +//.F qwtFloor125 +// Find the largest value out of {1,2,5}*10^n with an integer number n +// which is smaller than or equal to x +// +//.u Syntax +//.f double qwtFloor125(double x) +// +//.u Parameters +//.p double x +// +//------------------------------------------------------------ +double qwtFloor125( double x) +{ + double lx, rv; + double p10, fr; + double sign = ( x > 0) ? 1.0 : -1.0; + + if (x == 0.0) return 0.0; + + lx = log10(fabs(x)); + p10 = floor(lx); + fr = pow(10.0,lx - p10); + if (fr >= 10.0) + fr = 10.0; + else if (fr >= 5.0) + fr = 5.0; + else if (fr >= 2.0) + fr = 2.0; + else + fr = 1.0; + rv = fr * pow(10.0,p10); + return sign * rv; +} + + +//------------------------------------------------------------ +// +//.F qwtChkMono +// Checks if an array is a strictly monotonic sequence +// +//.u Syntax +//.f int qwtChkMono(double *array, int size) +// +//.u Parameters +//.p double *array -- pointer to a double array +// int size -- size of the array +// +//.u Return Value +//.t 0 -- sequence is not strictly monotonic +// 1 -- sequence is strictly monotonically increasing +// -1 -- sequence is strictly monotonically decreasing +// +//------------------------------------------------------------ +int qwtChkMono(double *array, int size) +{ + int rv, i; + + if (size < 2) return 0; + + rv = qwtSign(array[1] - array[0]); + for (i=1;i<size-1;i++) + { + if ( qwtSign(array[i+1] - array[i]) != rv ) + { + rv = 0; + break; + } + } + return rv; + +} + +//------------------------------------------------------------ +// +//.F qwtTwistArray +// Invert the order of array elements +// +//.u Syntax +//.f void qwtTwistArray(double *array, int size) +// +//.u Parameters +//.p double *array, int size +// +//------------------------------------------------------------ +void qwtTwistArray(double *array, int size) +{ + int itmp; + int i, s2; + double dtmp; + + s2 = size / 2; + + for (i=0; i < s2; i++) + { + itmp = size - 1 - i; + dtmp = array[i]; + array[i] = array[itmp]; + array[itmp] = dtmp; + } + +} + + +//------------------------------------------------------------ +// +//.F qwtLinSpace +// Create an array of equally spaced values +// +//.u Syntax +//.f void qwtLinSpace(double *array, int size, double xmin, double xmax) +// +//.u Parameters +//.p double *array -- where to put the values +// int size -- size of the array +// double xmin -- value associated with index 0 +// double xmax -- value associated with index (size-1) +// +//------------------------------------------------------------ +void qwtLinSpace(double *array, int size, double xmin, double xmax) +{ + int i, imax; + imax = size -1; + double step; + + if (size > 0) + { + array[0] = xmin; + array[imax] = xmax; + step = (xmax - xmin) / double(imax); + + for (i=1;i<imax;i++) + array[i] = xmin + double(i) * step; + } + +} + + +//------------------------------------------------------------ +// +//.F qwtLogSpace +// Create an array of logarithmically equally spaced values +// +//.u Syntax +//.f void qwtLogSpace(double *array, int size, double xmin, double xmax) +// +//.u Parameters +//.p double *array -- where to put the values +// int size -- size of the array +// double xmin -- value associated with index 0 +// double xmax -- value associated with index (size-1) +//------------------------------------------------------------ +void qwtLogSpace(double *array, int size, double xmin, double xmax) +{ + int i, imax; + + double lxmin,lxmax; + double lstep; + + imax = size -1; + + if ((xmin <= 0.0) || (xmax <= 0.0) || (size <= 0)) + return; + + array[0] = xmin; + array[imax] = xmax; + lxmin = log(xmin); + lxmax = log(xmax); + + lstep = (lxmax - lxmin) / double(imax); + + for (i=1; i<imax;i++) + array[i] = exp(lxmin + double(i) * lstep); + +} |