Math-expression evaluator

Shunting-yard algorithm for parsing mathematical expressions specified in infix notation implemented in C language

Changes from original version

• Context per evaluation to provide thread-safety support
• Support double instead of integer for all operations
• Add TEST_MODE evaluations
• Use error handling instead of exit calls
• Swap variables
• Support math operation (sqrt, sin, cos, floor, ceil) (pending)
• Context Config: scale, decimal (pending)

How to compile

gcc ./src/. -pthread -lm -o calc

How to run all tests

./calc TEST_MODE

Expected output

[TEST] Sample expressions ... 
[TEST] Sample expressions completed 
[TEST] Failure expressions ... 
[TEST] Failure expressions completed 
[TEST] Advanced expressions ... 
[TEST] Advanced expressions completed 

How to evaluate a math expression

./calc EVAL_MODE "12*0.0125"
Result: 0.15

./calc EVAL_MODE "12*0.0125+10^2"
Result: 100.1500000000

./calc EVAL_MODE "(12*0.0125+10^2)%45"
Result: 10.15

 ./calc EVAL_MODE "0.00012 - 0.0000012"
Result: 0.0001188

How to evaluate a math expression with variables

./calc EVAL_MODE "1+2+width" "width=3"
Result: 6.0

./calc EVAL_MODE "area-1+2+width" "width=3;area=100"
Result: 104.0000000000

./calc EVAL_MODE "(12%5)^3-(length+width)*2.45-area+12%5" "length=12.34;width=88.78;area=33.55"
Result: 0.15