공지사항:
2025년 4월 15일 전에 Earth Engine 사용을 위해 등록된 모든 비상업용 프로젝트는 Earth Engine 액세스를 유지하기 위해
비상업용 자격 요건을 인증해야 합니다.
ee.Number.expression
컬렉션을 사용해 정리하기
내 환경설정을 기준으로 콘텐츠를 저장하고 분류하세요.
숫자 표현식을 계산합니다.
사용 | 반환 값 |
---|
ee.Number.expression(expression, vars) | 숫자 |
인수 | 유형 | 세부정보 |
---|
expression | 문자열 | 평가할 수학 표현식 문자열입니다. 표준 산술, 불리언, 관계형 연산자 외에도 표현식은 Number의 모든 함수, 'vars' 사전에서 하위 요소를 추출하는 '.' 연산자, 수학 상수 Math.PI 및 Math.E를 지원합니다. |
vars | 사전, 기본값: null | 표현식에서 사용할 수 있는 명명된 값의 사전입니다. |
예
코드 편집기 (JavaScript)
// A dictionary of variables to use in expression.
var variables = {x: 5, y: 10};
// Arithmetic operators.
print('x + y',
ee.Number.expression('x + y', variables));
print('x - y',
ee.Number.expression('x - y', variables));
print('x * y',
ee.Number.expression('x * y', variables));
print('x / y',
ee.Number.expression('x / y', variables));
print('x ** y',
ee.Number.expression('x ** y', variables));
print('x % y',
ee.Number.expression('x % y', variables));
// Logical operators.
print('x || y',
ee.Number.expression('x || y', variables));
print('x && y',
ee.Number.expression('x && y', variables));
print('!(x)',
ee.Number.expression('!(x)', variables));
// Relational operators.
print('x > y',
ee.Number.expression('x > y', variables));
print('x >= y',
ee.Number.expression('x >= y', variables));
print('x < y',
ee.Number.expression('x < y', variables));
print('x <= y',
ee.Number.expression('x <= y', variables));
print('x == y',
ee.Number.expression('x == y', variables));
print('x != y',
ee.Number.expression('x != y', variables));
// Conditional (ternary) operator.
print('(x < y) ? 100 : 1000)',
ee.Number.expression('(x < y) ? 100 : 1000', variables));
// Constants in the expression.
print('100 * (x + y)',
ee.Number.expression('100 * (x + y)', variables));
// JavaScript Math constants.
print('Math.PI',
ee.Number.expression('Math.PI', null));
print('Math.E',
ee.Number.expression('Math.E', null));
// Dot notation to call on child elements.
print('Use dot notation to call on child elements',
ee.Number.expression('vals.x * vals.y', {vals: variables}));
// ee.Number functions.
print('Use ee.Number add: add(x, y)',
ee.Number.expression('add(x, y)', variables));
print('Use ee.Number add and subtract: subtract(add(x, y), 5)',
ee.Number.expression('subtract(add(x, y), 5)', variables));
Python 설정
Python API 및 geemap
를 사용한 대화형 개발에 관한 자세한 내용은
Python 환경 페이지를 참고하세요.
import ee
import geemap.core as geemap
Colab (Python)
# A dictionary of variables to use in expression.
variables = {'x': 5, 'y': 10}
# Arithmetic operators.
print('x + y:',
ee.Number.expression('x + y', variables).getInfo())
print('x - y:',
ee.Number.expression('x - y', variables).getInfo())
print('x * y:',
ee.Number.expression('x * y', variables).getInfo())
print('x / y:',
ee.Number.expression('x / y', variables).getInfo())
print('x ** y:',
ee.Number.expression('x ** y', variables).getInfo())
print('x % y:',
ee.Number.expression('x % y', variables).getInfo())
# Logical operators.
print('x || y:',
ee.Number.expression('x || y', variables).getInfo())
print('x && y:',
ee.Number.expression('x && y', variables).getInfo())
print('!(x):',
ee.Number.expression('!(x)', variables).getInfo())
# Relational operators.
print('x > y:',
ee.Number.expression('x > y', variables).getInfo())
print('x >= y:',
ee.Number.expression('x >= y', variables).getInfo())
print('x < y:',
ee.Number.expression('x < y', variables).getInfo())
print('x <= y:',
ee.Number.expression('x <= y', variables).getInfo())
print('x == y:',
ee.Number.expression('x == y', variables).getInfo())
print('x != y:',
ee.Number.expression('x != y', variables).getInfo())
# Conditional JavaScript (ternary) operator.
print('(x < y) ? 100 : 1000):',
ee.Number.expression('(x < y) ? 100 : 1000', variables).getInfo())
# Constants in the expression.
print('100 * (x + y):',
ee.Number.expression('100 * (x + y)', variables).getInfo())
# JavaScript Math constants.
print('Math.PI:',
ee.Number.expression('Math.PI', None).getInfo())
print('Math.E:',
ee.Number.expression('Math.E', None).getInfo())
# Dot notation to call on child elements.
print('Use dot notation to call on child elements:',
ee.Number.expression('vals.x * vals.y', {'vals': variables}).getInfo())
# ee.Number functions.
print('Use ee.Number add. add(x, y):',
ee.Number.expression('add(x, y)', variables).getInfo())
print('Use ee.Number add and subtract. subtract(add(x, y), 5):',
ee.Number.expression('subtract(add(x, y), 5)', variables).getInfo())
달리 명시되지 않는 한 이 페이지의 콘텐츠에는 Creative Commons Attribution 4.0 라이선스에 따라 라이선스가 부여되며, 코드 샘플에는 Apache 2.0 라이선스에 따라 라이선스가 부여됩니다. 자세한 내용은 Google Developers 사이트 정책을 참조하세요. 자바는 Oracle 및/또는 Oracle 계열사의 등록 상표입니다.
최종 업데이트: 2025-07-29(UTC)
[null,null,["최종 업데이트: 2025-07-29(UTC)"],[[["\u003cp\u003e\u003ccode\u003eee.Number.expression\u003c/code\u003e computes a numeric expression provided as a string.\u003c/p\u003e\n"],["\u003cp\u003eIt supports standard arithmetic, boolean, relational operators, as well as \u003ccode\u003eee.Number\u003c/code\u003e functions, and mathematical constants.\u003c/p\u003e\n"],["\u003cp\u003eA dictionary of variables can be passed to the function to be used within the expression.\u003c/p\u003e\n"],["\u003cp\u003eDot notation can be utilized within the expression to access child elements of variables provided in the dictionary.\u003c/p\u003e\n"]]],["`ee.Number.expression` evaluates a mathematical expression string. It accepts an `expression` string and an optional `vars` dictionary containing named values. The expression supports arithmetic, boolean, and relational operators, as well as functions found in `ee.Number` and constants like `Math.PI` and `Math.E`. Dot notation accesses nested dictionary elements. The function returns a numerical result, allowing complex computations. Examples include adding, subtracting, multiplying, applying logical operations, and conditional logic.\n"],null,["# ee.Number.expression\n\nComputes a numeric expression.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|----------------------------------------------|---------|\n| `ee.Number.expression(expression, `*vars*`)` | Number |\n\n| Argument | Type | Details |\n|--------------|---------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| `expression` | String | A mathematical expression string to be evaluated. In addition to the standard arithmetic, boolean and relational operators, expressions also support any function in Number, the '.' operator to extract child elements from the 'vars' dictionary, and mathematical constants Math.PI and Math.E. |\n| `vars` | Dictionary, default: null | A dictionary of named values that can be used in the expression. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// A dictionary of variables to use in expression.\nvar variables = {x: 5, y: 10};\n\n// Arithmetic operators.\nprint('x + y',\n ee.Number.expression('x + y', variables));\nprint('x - y',\n ee.Number.expression('x - y', variables));\nprint('x * y',\n ee.Number.expression('x * y', variables));\nprint('x / y',\n ee.Number.expression('x / y', variables));\nprint('x ** y',\n ee.Number.expression('x ** y', variables));\nprint('x % y',\n ee.Number.expression('x % y', variables));\n\n// Logical operators.\nprint('x || y',\n ee.Number.expression('x || y', variables));\nprint('x && y',\n ee.Number.expression('x && y', variables));\nprint('!(x)',\n ee.Number.expression('!(x)', variables));\n\n// Relational operators.\nprint('x \u003e y',\n ee.Number.expression('x \u003e y', variables));\nprint('x \u003e= y',\n ee.Number.expression('x \u003e= y', variables));\nprint('x \u003c y',\n ee.Number.expression('x \u003c y', variables));\nprint('x \u003c= y',\n ee.Number.expression('x \u003c= y', variables));\nprint('x == y',\n ee.Number.expression('x == y', variables));\nprint('x != y',\n ee.Number.expression('x != y', variables));\n\n// Conditional (ternary) operator.\nprint('(x \u003c y) ? 100 : 1000)',\n ee.Number.expression('(x \u003c y) ? 100 : 1000', variables));\n\n// Constants in the expression.\nprint('100 * (x + y)',\n ee.Number.expression('100 * (x + y)', variables));\n\n// JavaScript Math constants.\nprint('Math.PI',\n ee.Number.expression('Math.PI', null));\nprint('Math.E',\n ee.Number.expression('Math.E', null));\n\n// Dot notation to call on child elements.\nprint('Use dot notation to call on child elements',\n ee.Number.expression('vals.x * vals.y', {vals: variables}));\n\n// ee.Number functions.\nprint('Use ee.Number add: add(x, y)',\n ee.Number.expression('add(x, y)', variables));\nprint('Use ee.Number add and subtract: subtract(add(x, y), 5)',\n ee.Number.expression('subtract(add(x, y), 5)', variables));\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# A dictionary of variables to use in expression.\nvariables = {'x': 5, 'y': 10}\n\n# Arithmetic operators.\nprint('x + y:',\n ee.Number.expression('x + y', variables).getInfo())\nprint('x - y:',\n ee.Number.expression('x - y', variables).getInfo())\nprint('x * y:',\n ee.Number.expression('x * y', variables).getInfo())\nprint('x / y:',\n ee.Number.expression('x / y', variables).getInfo())\nprint('x ** y:',\n ee.Number.expression('x ** y', variables).getInfo())\nprint('x % y:',\n ee.Number.expression('x % y', variables).getInfo())\n\n# Logical operators.\nprint('x || y:',\n ee.Number.expression('x || y', variables).getInfo())\nprint('x && y:',\n ee.Number.expression('x && y', variables).getInfo())\nprint('!(x):',\n ee.Number.expression('!(x)', variables).getInfo())\n\n# Relational operators.\nprint('x \u003e y:',\n ee.Number.expression('x \u003e y', variables).getInfo())\nprint('x \u003e= y:',\n ee.Number.expression('x \u003e= y', variables).getInfo())\nprint('x \u003c y:',\n ee.Number.expression('x \u003c y', variables).getInfo())\nprint('x \u003c= y:',\n ee.Number.expression('x \u003c= y', variables).getInfo())\nprint('x == y:',\n ee.Number.expression('x == y', variables).getInfo())\nprint('x != y:',\n ee.Number.expression('x != y', variables).getInfo())\n\n# Conditional JavaScript (ternary) operator.\nprint('(x \u003c y) ? 100 : 1000):',\n ee.Number.expression('(x \u003c y) ? 100 : 1000', variables).getInfo())\n\n# Constants in the expression.\nprint('100 * (x + y):',\n ee.Number.expression('100 * (x + y)', variables).getInfo())\n\n# JavaScript Math constants.\nprint('Math.PI:',\n ee.Number.expression('Math.PI', None).getInfo())\nprint('Math.E:',\n ee.Number.expression('Math.E', None).getInfo())\n\n# Dot notation to call on child elements.\nprint('Use dot notation to call on child elements:',\n ee.Number.expression('vals.x * vals.y', {'vals': variables}).getInfo())\n\n# ee.Number functions.\nprint('Use ee.Number add. add(x, y):',\n ee.Number.expression('add(x, y)', variables).getInfo())\nprint('Use ee.Number add and subtract. subtract(add(x, y), 5):',\n ee.Number.expression('subtract(add(x, y), 5)', variables).getInfo())\n```"]]