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To convert an integer to floating point, use the function float
.
This returns number converted to floating point. If number is already a floating point number,
float
returns it unchanged.
There are four functions to convert floating point numbers to integers; they differ in how they round. These functions accept integer arguments also, and return such arguments unchanged.
This returns number, converted to an integer by rounding towards zero.
(truncate 1.2) => 1 (truncate 1.7) => 1 (truncate -1.2) => -1 (truncate -1.7) => -1
This returns number, converted to an integer by rounding downward (towards negative infinity).
If divisor is specified,
floor
divides number by divisor and then converts to an integer; this uses the kind of division operation that corresponds tomod
, rounding downward. Anarith-error
results if divisor is 0.(floor 1.2) => 1 (floor 1.7) => 1 (floor -1.2) => -2 (floor -1.7) => -2 (floor 5.99 3) => 1
This returns number, converted to an integer by rounding upward (towards positive infinity).
(ceiling 1.2) => 2 (ceiling 1.7) => 2 (ceiling -1.2) => -1 (ceiling -1.7) => -1
This returns number, converted to an integer by rounding towards the nearest integer. Rounding a value equidistant between two integers may choose the integer closer to zero, or it may prefer an even integer, depending on your machine.
(round 1.2) => 1 (round 1.7) => 2 (round -1.2) => -1 (round -1.7) => -2