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19025d77ad
Reorganized. Created a new top level include directory that will hold all of Trick's header files. Moved all of the Trick headers to this directory. Created a libexec directory that holds all of the executables that users don't need to execute directly. Changed all of the executables remaining in bin to start with "trick-". In the sim_services directories changed all source files to find the Trick headers in their new location. Since all of the include files are gone in sim_services, removed the src directories as well, moving all of the source files up a level. Moved the makefiles, docs, man, and other architecture independent files into a top level share directory. Renamed lib_${TRICK_HOST_CPU} to lib64 or lib depending on the platform we're currently on.
refs #63
54 lines
2.0 KiB
C
54 lines
2.0 KiB
C
/*
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PURPOSE: (Given an input value 'x', return a value 'y' in the range of zero to one, based on a function with the
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following properties: 1 - zero slope at zero and at one, 2 - continous, 3 - parabolic between at both ends, 4 - and
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not necessarily symmetric.)
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PROGRAMMERS: (((Robert W. Bailey) (LinCom Corp) (3/22/91) (Trick-CR-00000) (Initial release))) */
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#include "trick/trick_math.h"
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double dS_function( /* Return: -- 0.0 <= value <= 1.0 */
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double x, /* In: 'x' parameter */
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double zero_point, /* In: 'x' value where 's' function returns 0.0 */
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double mid_point, /* In: 'x' value where 's' function returns 0.5 */
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double one_point, /* In: 'x' value where 's' function returns 1.0 */
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double sign)
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{ /* In: 'x' axis sign evaluation flag: -1 = evaluate -'X' axis, 1 = evaluate +'X'
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axis */
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double temp, temp1;
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double value;
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if (sign > 0) {
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if (x >= one_point)
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value = 1.0;
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else if (x <= zero_point)
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value = 0.0;
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else if (zero_point < x && x < mid_point) {
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temp = x - zero_point;
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temp1 = mid_point - zero_point;
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value = temp * temp / (2.0 * temp1 * temp1);
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} else {
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temp = x - one_point;
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temp1 = one_point - mid_point;
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value = 1.0 - (temp * temp / (2.0 * temp1 * temp1));
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}
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} else {
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if (x <= one_point)
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value = 1.0;
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else if (x >= zero_point)
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value = 0.0;
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else if (mid_point < x && x < zero_point) {
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temp = x - zero_point;
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temp1 = mid_point - zero_point;
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value = temp * temp / (2.0 * temp1 * temp1);
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} else {
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temp = x - one_point;
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temp1 = one_point - mid_point;
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value = 1.0 - (temp * temp / (2.0 * temp1 * temp1));
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}
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}
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return (value);
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}
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