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ee.Number.toInt8
使用集合让一切井井有条
根据您的偏好保存内容并对其进行分类。
将输入值强制转换为有符号的 8 位整数。
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)
print('Number:', number.getInfo())
int8_number = number.toInt8()
print('Number cast to int8:', int8_number.getInfo())
"""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)
print('Floating point value:', float_number.getInfo())
float_to_int8 = float_number.toInt8()
print('Floating point value cast to int8:', float_to_int8.getInfo())
# 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)
print('Greater than int8 max:', out_of_range_hi.getInfo())
out_of_range_hi_to_int8 = out_of_range_hi.toInt8()
print('Greater than int8 max cast to int8 becomes int8 max:',
out_of_range_hi_to_int8.getInfo())
# 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)
print('Less than int8 min:', out_of_range_lo.getInfo())
out_of_range_lo_to_int8 = out_of_range_lo.toInt8()
print('Less than int8 min cast to int8 becomes int8 min:',
out_of_range_lo_to_int8.getInfo())
如未另行说明,那么本页面中的内容已根据知识共享署名 4.0 许可获得了许可,并且代码示例已根据 Apache 2.0 许可获得了许可。有关详情,请参阅 Google 开发者网站政策。Java 是 Oracle 和/或其关联公司的注册商标。
最后更新时间 (UTC):2025-07-26。
[null,null,["最后更新时间 (UTC):2025-07-26。"],[[["\u003cp\u003e\u003ccode\u003eNumber.toInt8()\u003c/code\u003e casts a given number to a signed 8-bit integer, which has a valid range of -128 to 127.\u003c/p\u003e\n"],["\u003cp\u003eNumbers exceeding the maximum value of an 8-bit integer will be truncated to the maximum value (127).\u003c/p\u003e\n"],["\u003cp\u003eNumbers falling below the minimum value of an 8-bit integer will be truncated to the minimum value (-128).\u003c/p\u003e\n"],["\u003cp\u003eFloating-point numbers cast to signed 8-bit integers will lose their decimal precision.\u003c/p\u003e\n"]]],["The `toInt8()` method casts a numerical input to a signed 8-bit integer, with a range of -128 to 127. Floating-point numbers lose their decimal precision during this cast. Numbers exceeding the maximum range (127) are converted to 127, and those below the minimum (-128) become -128. The function takes a Number as input and returns a Number that is an 8 bit signed integer.\n"],null,["# ee.Number.toInt8\n\nCasts the input value to a signed 8-bit integer.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|-------------------|---------|\n| Number.toInt8`()` | Number |\n\n| Argument | Type | Details |\n|---------------|--------|------------------|\n| this: `input` | Number | The input value. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// Cast a number to signed 8-bit integer: [-128, 127].\nvar number = ee.Number(100);\nprint('Number:', number);\n\nvar int8Number = number.toInt8();\nprint('Number cast to int8:', int8Number);\n\n\n/**\n * Casting numbers to int8 that are outside of its range and precision can\n * modify the resulting value, note the behavior of the following scenarios.\n */\n\n// A floating point number cast to int8 loses decimal precision.\nvar float = ee.Number(1.7);\nprint('Floating point value:', float);\n\nvar floatToInt8 = float.toInt8();\nprint('Floating point value cast to int8:', floatToInt8);\n\n// A number greater than int8 range max cast to int8 becomes int8 range max.\nvar INT8_MAX = 127;\nvar outOfRangeHi = ee.Number(INT8_MAX + 12345);\nprint('Greater than int8 max:', outOfRangeHi);\n\nvar outOfRangeHiToInt8 = outOfRangeHi.toInt8();\nprint('Greater than int8 max cast to int8 becomes int8 max:', outOfRangeHiToInt8);\n\n// A number greater than int8 range min cast to int8 becomes int8 range min.\nvar INT8_MIN = -128;\nvar outOfRangeLo = ee.Number(INT8_MIN - 12345);\nprint('Less than int8 min:', outOfRangeLo);\n\nvar outOfRangeLoToInt8 = outOfRangeLo.toInt8();\nprint('Less than int8 min cast to int8 becomes int8 min:', outOfRangeLoToInt8);\n```\nPython setup\n\nSee the [Python Environment](/earth-engine/guides/python_install) page for information on the Python API and using\n`geemap` for interactive development. \n\n```python\nimport ee\nimport geemap.core as geemap\n```\n\n### Colab (Python)\n\n```python\n# Cast a number to signed 8-bit integer: [-128, 127].\nnumber = ee.Number(100)\nprint('Number:', number.getInfo())\n\nint8_number = number.toInt8()\nprint('Number cast to int8:', int8_number.getInfo())\n\n\n\"\"\"Casting numbers to int8 that are outside of its range and precision can\nmodify the resulting value, note the behavior of the following scenarios.\n\"\"\"\n\n# A floating point number cast to int8 loses decimal precision.\nfloat_number = ee.Number(1.7)\nprint('Floating point value:', float_number.getInfo())\n\nfloat_to_int8 = float_number.toInt8()\nprint('Floating point value cast to int8:', float_to_int8.getInfo())\n\n# A number greater than int8 range max cast to int8 becomes int8 range max.\nINT8_MAX = 127\nout_of_range_hi = ee.Number(INT8_MAX + 12345)\nprint('Greater than int8 max:', out_of_range_hi.getInfo())\n\nout_of_range_hi_to_int8 = out_of_range_hi.toInt8()\nprint('Greater than int8 max cast to int8 becomes int8 max:',\n out_of_range_hi_to_int8.getInfo())\n\n# A number greater than int8 range min cast to int8 becomes int8 range min.\nINT8_MIN = -128\nout_of_range_lo = ee.Number(INT8_MIN - 12345)\nprint('Less than int8 min:', out_of_range_lo.getInfo())\n\nout_of_range_lo_to_int8 = out_of_range_lo.toInt8()\nprint('Less than int8 min cast to int8 becomes int8 min:',\n out_of_range_lo_to_int8.getInfo())\n```"]]