d.histogram: Initialize range_dmin and range_dmax to fix uninitialize value warnings in bar.c

[ShubhamDesai]

This pull request addresses uninitialized value warnings in the bar.c file.

Fixed Issues: bar.c:221:58: warning: The right operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] range_dmin + i * (range_dmax - range_dmin) / nsteps;

bar.c:275:58: warning: The right operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] range_dmin + i * (range_dmax - range_dmin) / nsteps;

bar.c:312:53: warning: The right operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] dmin = range_dmin + i * (range_dmax - range_dmin) / nsteps;

bar.c:221:58: warning: The left operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] range_dmin + i * (range_dmax - range_dmin) / nsteps;

bar.c:275:58: warning: The left operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] range_dmin + i * (range_dmax - range_dmin) / nsteps;

bar.c:312:53: warning: The left operand of '-' is a garbage value [core.UndefinedBinaryOperatorResult] dmin = range_dmin + i * (range_dmax - range_dmin) / nsteps;

• Warning: The right operand of '-' is a garbage value.
• Warning: The left operand of '-' is a garbage value.

Changes Made:

• Initialize range_dmin and range_dmax to 0 to prevent the use of uninitialized values in calculations.

Code Changes

• DCELL dmax, range_dmin, range_dmax , dmin, dval; To
• DCELL dmax, range_dmin = 0, range_dmax = 0, dmin, dval;