Objective C rounding, float Processing

Nslog (@ "square: %. F", POW (3, 2); // result 9

Nslog (@ "Top Rounding: %. F", Ceil (3.000000000001); // Result 4

Nslog (@ "Rounding: %. F", round (3.30); // result 3

Nslog (@ "drop in: % 0.f", floor (232.90); // result 232

Nslog (@ "minimum value: % 0.02f", fmin (3.22, 22.22); // result 3.22

Nslog (@ "maximum value: % 0.02f", fmax (3.22, 22.34); // result 22.34

Nslog (@ "absolute value: % 0.f", FABS (-10.00); // result 10

 

Here is a small tip:

1: If you want to round 3.321 to 3.32, that is, the last two digits of the decimal point, you can do this.

 

Nslog (@ "% 0.02f", round (3.321*100)/100); // result 3.21

Nslog (@ "% 0.02f", round (3.321); // result 3.00

The printed results are different.

 

As an extension of ansic, objective-C uses some mathematical constant macros and mathematical functions defined in the header file <math. h> in the C standard library for basic operations.

Mathematical constants:
# Define m_e 2.71828182845904523536028747135266250 // E
# Define m_log2e 1.44269504088896340735992468100189214 // log 2e
# Define m_log10e 0.434294481903251827651128918916605082 // log 10E
# Define m_ln2 0.693147180559945309417232121458176568 // log E2
# Define m_ln10 2.30258509299404568401799145468436421 // log E10
# Define m_pi 3.14159265358979323846264338327950288 // pi
# Define m_pi_2 1.57079632679489661923132169163975144 // PI/2
# Define m_pi_4 0.785398163397448309615660845819875721 // PI/4
# Define m_0000pi 0.318309886183790671537767526745028724 // 1/PI
# Define m_2_pi 0.636619772367581343075535053490057448 // 2/PI
# Define m_2_sqrtpi 1.12837916709551257389615890312154517 // 2/SQRT (PI)
# Define m_sqrt2 1.41421356237309504880168872420969808 // SQRT (2)
# Define m_sqrt1_2 0.707106781186547524400844362104849039 // 1/SQRT (2)

 

 

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