ee.Number.toInt8

将输入值强制转换为有符号的 8 位整数。

用法	返回
Number.toInt8()	数字

参数	类型	详细信息
此：input	数字	输入值。

示例

代码编辑器 (JavaScript)

// Cast a number to signed 8-bit integer: [-128, 127].
var number = ee.Number(100);
print('Number:', number);

var int8Number = number.toInt8();
print('Number cast to int8:', int8Number);


/**
 * Casting numbers to int8 that are outside of its range and precision can
 * modify the resulting value, note the behavior of the following scenarios.
 */

// A floating point number cast to int8 loses decimal precision.
var float = ee.Number(1.7);
print('Floating point value:', float);

var floatToInt8 = float.toInt8();
print('Floating point value cast to int8:', floatToInt8);

// A number greater than int8 range max cast to int8 becomes int8 range max.
var INT8_MAX = 127;
var outOfRangeHi = ee.Number(INT8_MAX + 12345);
print('Greater than int8 max:', outOfRangeHi);

var outOfRangeHiToInt8 = outOfRangeHi.toInt8();
print('Greater than int8 max cast to int8 becomes int8 max:', outOfRangeHiToInt8);

// A number greater than int8 range min cast to int8 becomes int8 range min.
var INT8_MIN = -128;
var outOfRangeLo = ee.Number(INT8_MIN - 12345);
print('Less than int8 min:', outOfRangeLo);

var outOfRangeLoToInt8 = outOfRangeLo.toInt8();
print('Less than int8 min cast to int8 becomes int8 min:', outOfRangeLoToInt8);

Python 设置

如需了解 Python API 和如何使用 geemap 进行交互式开发，请参阅 Python 环境页面。

import ee
import geemap.core as geemap

Colab (Python)

# Cast a number to signed 8-bit integer: [-128, 127].
number = ee.Number(100)
display('Number:', number)

int8_number = number.toInt8()
display('Number cast to int8:', int8_number)


"""Casting numbers to int8 that are outside of its range and precision can
modify the resulting value, note the behavior of the following scenarios.
"""

# A floating point number cast to int8 loses decimal precision.
float_number = ee.Number(1.7)
display('Floating point value:', float_number)

float_to_int8 = float_number.toInt8()
display('Floating point value cast to int8:', float_to_int8)

# A number greater than int8 range max cast to int8 becomes int8 range max.
INT8_MAX = 127
out_of_range_hi = ee.Number(INT8_MAX + 12345)
display('Greater than int8 max:', out_of_range_hi)

out_of_range_hi_to_int8 = out_of_range_hi.toInt8()
display('Greater than int8 max cast to int8 becomes int8 max:',
        out_of_range_hi_to_int8)

# A number greater than int8 range min cast to int8 becomes int8 range min.
INT8_MIN = -128
out_of_range_lo = ee.Number(INT8_MIN - 12345)
display('Less than int8 min:', out_of_range_lo)

out_of_range_lo_to_int8 = out_of_range_lo.toInt8()
display('Less than int8 min cast to int8 becomes int8 min:',
        out_of_range_lo_to_int8)