算術関数
Cloud Firestore のすべての算術関数には次の挙動があります。
- いずれかの入力パラメータが
NULLの場合、NULLと評価されます。 - いずれかの引数が
NaNの場合、NaNと評価されます。 - オーバーフローまたはアンダーフローが発生した場合は、エラーが発生します。
また、算術関数が異なる型の複数の数値引数を取る場合(add(5.0, 6) など)、Cloud Firestore は引数を最も広い入力型に暗黙的に変換します。INT32 の入力のみが指定されている場合、戻り値の型は INT64 になります。
| 名前 | 説明 |
ABS
|
number の絶対値を返します。
|
ADD
|
x + y の値を返します。 |
SUBTRACT
|
x - y の値を返します。 |
MULTIPLY
|
x * y の値を返します。 |
DIVIDE
|
x / y の値を返します。 |
MOD
|
x / y の除算の余りを返します。
|
CEIL
|
number の天井関数を返します。
|
FLOOR
|
number の床関数を返します。
|
ROUND
|
number を小数点以下 places 桁に丸めます。
|
POW
|
base^exponent の値を返します。 |
SQRT
|
number の平方根を返します。
|
EXP
|
オイラー数を exponent のべき乗で返します。
|
LN
|
number の自然対数を返します。
|
LOG
|
number の対数を返します。
|
LOG10
|
10 を底とする number の対数を返します。
|
RAND
|
疑似乱数の浮動小数点数を返します。 |
ABS
構文:
abs[N <: INT32 | INT64 | FLOAT64](number: N) -> N
説明:
number の絶対値を返します。
- この関数で
INT32またはINT64の値がオーバーフローする場合はエラーをスローします。
例:
| 数値 | abs(number) |
|---|---|
| 10 | 10 |
| -10 | 10 |
| 10L | 10L |
| -0.0 | 0.0 |
| 10.5 | 10.5 |
| -10.5 | 10.5 |
| -231 | [error] |
| -263 | [error] |
追加
構文:
add[N <: INT32 | INT64 | FLOAT64](x: N, y: N) -> N
説明:
x + y の値を返します。
例:
| x | y | add(x, y) |
|---|---|---|
| 20 | 3 | 23 |
| 10.0 | 1 | 11.0 |
| 22.5 | 2.0 | 24.5 |
| INT64.MAX | 1 | [error] |
| INT64.MIN | -1 | [error] |
Web
const result = await execute(db.pipeline() .collection("books") .select(field("soldBooks").add(field("unsoldBooks")).as("totalBooks")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("soldBooks").add(Field("unsoldBooks")).as("totalBooks")]) .execute()
Kotlin
val result = db.pipeline() .collection("books") .select(Expression.add(field("soldBooks"), field("unsoldBooks")).alias("totalBooks")) .execute()
Java
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(Expression.add(field("soldBooks"), field("unsoldBooks")).alias("totalBooks")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("soldBooks").add(Field.of("unsoldBooks")).as_("totalBooks")) .execute() )
SUBTRACT
構文:
subtract[N <: INT32 | INT64 | FLOAT64](x: N, y: N) -> N
説明:
x - y の値を返します。
例:
| x | y | subtract(x, y) |
|---|---|---|
| 20 | 3 | 17 |
| 10.0 | 1 | 9.0 |
| 22.5 | 2.0 | 20.5 |
| INT64.MAX | -1 | [error] |
| INT64.MIN | 1 | [error] |
Web
const storeCredit = 7; const result = await execute(db.pipeline() .collection("books") .select(field("price").subtract(constant(storeCredit)).as("totalCost")) );
Swift
let storeCredit = 7 let result = try await db.pipeline() .collection("books") .select([Field("price").subtract(Constant(storeCredit)).as("totalCost")]) .execute()
Kotlin
val storeCredit = 7 val result = db.pipeline() .collection("books") .select(Expression.subtract(field("price"), storeCredit).alias("totalCost")) .execute()
Java
int storeCredit = 7; Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(Expression.subtract(field("price"), storeCredit).alias("totalCost")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field store_credit = 7 result = ( client.pipeline() .collection("books") .select(Field.of("price").subtract(store_credit).as_("totalCost")) .execute() )
MULTIPLY
構文:
multiply[N <: INT32 | INT64 | FLOAT64](x: N, y: N) -> N
説明:
x * y の値を返します。
例:
| x | y | multiply(x, y) |
|---|---|---|
| 20 | 3 | 60 |
| 10.0 | 1 | 10.0 |
| 22.5 | 2.0 | 45.0 |
| INT64.MAX | 2 | [error] |
| INT64.MIN | 2 | [error] |
| FLOAT64.MAX | FLOAT64.MAX | +inf |
Web
const result = await execute(db.pipeline() .collection("books") .select(field("price").multiply(field("soldBooks")).as("revenue")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("price").multiply(Field("soldBooks")).as("revenue")]) .execute()
Kotlin
val result = db.pipeline() .collection("books") .select(Expression.multiply(field("price"), field("soldBooks")).alias("revenue")) .execute()
Java
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(Expression.multiply(field("price"), field("soldBooks")).alias("revenue")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("price").multiply(Field.of("soldBooks")).as_("revenue")) .execute() )
DIVIDE
構文:
divide[N <: INT32 | INT64 | FLOAT64](x: N, y: N) -> N
説明:
x / y の値を返します。 整数の除算では切り捨てが行われます。
例:
| x | y | divide(x, y) |
|---|---|---|
| 20 | 3 | 6 |
| 10.0 | 3 | 3.333... |
| 22.5 | 2 | 11.25 |
| 10 | 0 | [error] |
| 1.0 | 0.0 | +inf |
| -1.0 | 0.0 | -inf |
Web
const result = await execute(db.pipeline() .collection("books") .select(field("ratings").divide(field("soldBooks")).as("reviewRate")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("ratings").divide(Field("soldBooks")).as("reviewRate")]) .execute()
Kotlin
val result = db.pipeline() .collection("books") .select(Expression.divide(field("ratings"), field("soldBooks")).alias("reviewRate")) .execute()
Java
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(Expression.divide(field("ratings"), field("soldBooks")).alias("reviewRate")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("ratings").divide(Field.of("soldBooks")).as_("reviewRate")) .execute() )
MOD
構文:
mod[N <: INT32 | INT64 | FLOAT64](x: N, y: N) -> N
説明:
x / y の余りを返します。
- 整数型(
INT64)の場合、yがゼロのときにerrorをスローします。 - 浮動小数点型(
FLOAT64)の場合、yがゼロのときにNaNを返します。
例:
| x | y | mod(x, y) |
|---|---|---|
| 20 | 3 | 2 |
| -10 | 3 | -1 |
| 10 | -3 | 1 |
| -10 | -3 | -1 |
| 10 | 1 | 0 |
| 22.5 | 2 | 0.5 |
| 22.5 | 0.0 | NaN |
| 25 | 0 | [error] |
Web
const displayCapacity = 1000; const result = await execute(db.pipeline() .collection("books") .select(field("unsoldBooks").mod(constant(displayCapacity)).as("warehousedBooks")) );
Swift
let displayCapacity = 1000 let result = try await db.pipeline() .collection("books") .select([Field("unsoldBooks").mod(Constant(displayCapacity)).as("warehousedBooks")]) .execute()
Kotlin
val displayCapacity = 1000 val result = db.pipeline() .collection("books") .select(Expression.mod(field("unsoldBooks"), displayCapacity).alias("warehousedBooks")) .execute()
Java
int displayCapacity = 1000; Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(Expression.mod(field("unsoldBooks"), displayCapacity).alias("warehousedBooks")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field display_capacity = 1000 result = ( client.pipeline() .collection("books") .select(Field.of("unsoldBooks").mod(display_capacity).as_("warehousedBooks")) .execute() )
CEIL
構文:
ceil[N <: INT32 | INT64 | FLOAT64](number: N) -> N
説明:
number 以上の最小の整数値を返します。
例:
| 数値 | ceil(number) |
|---|---|
| 20 | 20 |
| 10 | 10 |
| 0 | 0 |
| 24L | 24L |
| -0.4 | -0.0 |
| 0.4 | 1.0 |
| 22.5 | 23.0 |
+inf |
+inf |
-inf |
-inf |
Web
const booksPerShelf = 100; const result = await execute(db.pipeline() .collection("books") .select( field("unsoldBooks").divide(constant(booksPerShelf)).ceil().as("requiredShelves") ) );
Swift
let booksPerShelf = 100 let result = try await db.pipeline() .collection("books") .select([ Field("unsoldBooks").divide(Constant(booksPerShelf)).ceil().as("requiredShelves") ]) .execute()
Kotlin
val booksPerShelf = 100 val result = db.pipeline() .collection("books") .select( Expression.divide(field("unsoldBooks"), booksPerShelf).ceil().alias("requiredShelves") ) .execute()
Java
int booksPerShelf = 100; Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select( Expression.divide(field("unsoldBooks"), booksPerShelf).ceil().alias("requiredShelves") ) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field books_per_shelf = 100 result = ( client.pipeline() .collection("books") .select( Field.of("unsoldBooks") .divide(books_per_shelf) .ceil() .as_("requiredShelves") ) .execute() )
FLOOR
構文:
floor[N <: INT32 | INT64 | FLOAT64](number: N) -> N
説明:
number 以下の最大の整数値を返します。
例:
| 数値 | floor(number) |
|---|---|
| 20 | 20 |
| 10 | 10 |
| 0 | 0 |
| 2147483648 | 2147483648 |
| -0.4 | -1.0 |
| 0.4 | 0.0 |
| 22.5 | 22.0 |
+inf |
+inf |
-inf |
-inf |
Web
const result = await execute(db.pipeline() .collection("books") .addFields( field("wordCount").divide(field("pages")).floor().as("wordsPerPage") ) );
Swift
let result = try await db.pipeline() .collection("books") .addFields([ Field("wordCount").divide(Field("pages")).floor().as("wordsPerPage") ]) .execute()
Kotlin
val result = db.pipeline() .collection("books") .addFields( Expression.divide(field("wordCount"), field("pages")).floor().alias("wordsPerPage") ) .execute()
Java
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .addFields( Expression.divide(field("wordCount"), field("pages")).floor().alias("wordsPerPage") ) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .add_fields( Field.of("wordCount").divide(Field.of("pages")).floor().as_("wordsPerPage") ) .execute() )
ROUND
構文:
round[N <: INT32 | INT64 | FLOAT64 | DECIMAL128](number: N) -> N
round[N <: INT32 | INT64 | FLOAT64 | DECIMAL128](number: N, places: INT64) -> N
説明:
number の places 桁を丸めます。places が正の場合は小数点の右側の桁を、負の場合は小数点の左側の桁を丸めます。
numberのみが指定されている場合は、最も近い整数値に丸めます。- 中間の値の場合は、ゼロから遠ざかるように丸めます。
- 負の
places値で丸め処理を行った結果、オーバーフローが発生した場合は、errorがスローされます。
例:
| 数値 | 桁数 | round(number, places) |
|---|---|---|
| 15.5 | 0 | 16.0 |
| -15.5 | 0 | -16.0 |
| 15 | 1 | 15 |
| 15 | 0 | 15 |
| 15 | -1 | 20 |
| 15 | -2 | 0 |
| 15.48924 | 1 | 15.5 |
| 231-1 | -1 | [error] |
| 263-1L | -1 | [error] |
Web
const result = await execute(db.pipeline() .collection("books") .select(field("soldBooks").multiply(field("price")).round().as("partialRevenue")) .aggregate(field("partialRevenue").sum().as("totalRevenue")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("soldBooks").multiply(Field("price")).round().as("partialRevenue")]) .aggregate([Field("partialRevenue").sum().as("totalRevenue")]) .execute()
Kotlin
val result = db.pipeline() .collection("books") .select(Expression.multiply(field("soldBooks"), field("price")).round().alias("partialRevenue")) .aggregate(AggregateFunction.sum("partialRevenue").alias("totalRevenue")) .execute()
Java
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(Expression.multiply(field("soldBooks"), field("price")).round().alias("partialRevenue")) .aggregate(AggregateFunction.sum("partialRevenue").alias("totalRevenue")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select( Field.of("soldBooks") .multiply(Field.of("price")) .round() .as_("partialRevenue") ) .aggregate(Field.of("partialRevenue").sum().as_("totalRevenue")) .execute() )
POW
構文:
pow(base: FLOAT64, exponent: FLOAT64) -> FLOAT64
説明:
base を exponent でべき乗した値を返します。
base <= 0とexponentが負の場合、エラーをスローします。任意の
exponentについて、pow(1, exponent)は 1 です。任意の
baseについて、pow(base, 0)は 1 です。
例:
| 底 | 指数 | pow(base, exponent) |
|---|---|---|
| 2 | 3 | 8.0 |
| 2 | -3 | 0.125 |
+inf |
0 | 1.0 |
| 1 | +inf |
1.0 |
| -1 | 0.5 | [error] |
| 0 | -1 | [error] |
Web
const googleplex = { latitude: 37.4221, longitude: 122.0853 }; const result = await execute(db.pipeline() .collection("cities") .addFields( field("lat").subtract(constant(googleplex.latitude)) .multiply(111 /* km per degree */) .pow(2) .as("latitudeDifference"), field("lng").subtract(constant(googleplex.longitude)) .multiply(111 /* km per degree */) .pow(2) .as("longitudeDifference") ) .select( field("latitudeDifference").add(field("longitudeDifference")).sqrt() // Inaccurate for large distances or close to poles .as("approximateDistanceToGoogle") ) );
Swift
let googleplex = CLLocation(latitude: 37.4221, longitude: 122.0853) let result = try await db.pipeline() .collection("cities") .addFields([ Field("lat").subtract(Constant(googleplex.coordinate.latitude)) .multiply(111 /* km per degree */) .pow(2) .as("latitudeDifference"), Field("lng").subtract(Constant(googleplex.coordinate.latitude)) .multiply(111 /* km per degree */) .pow(2) .as("longitudeDifference") ]) .select([ Field("latitudeDifference").add(Field("longitudeDifference")).sqrt() // Inaccurate for large distances or close to poles .as("approximateDistanceToGoogle") ]) .execute()
Kotlin
val googleplex = GeoPoint(37.4221, -122.0853) val result = db.pipeline() .collection("cities") .addFields( field("lat").subtract(googleplex.latitude) .multiply(111 /* km per degree */) .pow(2) .alias("latitudeDifference"), field("lng").subtract(googleplex.longitude) .multiply(111 /* km per degree */) .pow(2) .alias("longitudeDifference") ) .select( field("latitudeDifference").add(field("longitudeDifference")).sqrt() // Inaccurate for large distances or close to poles .alias("approximateDistanceToGoogle") ) .execute()
Java
GeoPoint googleplex = new GeoPoint(37.4221, -122.0853); Task<Pipeline.Snapshot> result = db.pipeline() .collection("cities") .addFields( field("lat").subtract(googleplex.getLatitude()) .multiply(111 /* km per degree */) .pow(2) .alias("latitudeDifference"), field("lng").subtract(googleplex.getLongitude()) .multiply(111 /* km per degree */) .pow(2) .alias("longitudeDifference") ) .select( field("latitudeDifference").add(field("longitudeDifference")).sqrt() // Inaccurate for large distances or close to poles .alias("approximateDistanceToGoogle") ) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field googleplexLat = 37.4221 googleplexLng = -122.0853 result = ( client.pipeline() .collection("cities") .add_fields( Field.of("lat") .subtract(googleplexLat) .multiply(111) # km per degree .pow(2) .as_("latitudeDifference"), Field.of("lng") .subtract(googleplexLng) .multiply(111) # km per degree .pow(2) .as_("longitudeDifference"), ) .select( Field.of("latitudeDifference") .add(Field.of("longitudeDifference")) .sqrt() # Inaccurate for large distances or close to poles .as_("approximateDistanceToGoogle") ) .execute() )
SQRT
構文:
sqrt[N <: FLOAT64 | DECIMAL128](number: N) -> N
説明:
number の平方根を返します。
numberが負の場合、errorをスローします。
例:
| 数値 | sqrt(number) |
|---|---|
| 25 | 5.0 |
| 12.002 | 3.464... |
| 0.0 | 0.0 |
NaN |
NaN |
+inf |
+inf |
-inf |
[error] |
x < 0 |
[error] |
Web
const googleplex = { latitude: 37.4221, longitude: 122.0853 }; const result = await execute(db.pipeline() .collection("cities") .addFields( field("lat").subtract(constant(googleplex.latitude)) .multiply(111 /* km per degree */) .pow(2) .as("latitudeDifference"), field("lng").subtract(constant(googleplex.longitude)) .multiply(111 /* km per degree */) .pow(2) .as("longitudeDifference") ) .select( field("latitudeDifference").add(field("longitudeDifference")).sqrt() // Inaccurate for large distances or close to poles .as("approximateDistanceToGoogle") ) );
Swift
let googleplex = CLLocation(latitude: 37.4221, longitude: 122.0853) let result = try await db.pipeline() .collection("cities") .addFields([ Field("lat").subtract(Constant(googleplex.coordinate.latitude)) .multiply(111 /* km per degree */) .pow(2) .as("latitudeDifference"), Field("lng").subtract(Constant(googleplex.coordinate.latitude)) .multiply(111 /* km per degree */) .pow(2) .as("longitudeDifference") ]) .select([ Field("latitudeDifference").add(Field("longitudeDifference")).sqrt() // Inaccurate for large distances or close to poles .as("approximateDistanceToGoogle") ]) .execute()
Kotlin
val googleplex = GeoPoint(37.4221, -122.0853) val result = db.pipeline() .collection("cities") .addFields( field("lat").subtract(googleplex.latitude) .multiply(111 /* km per degree */) .pow(2) .alias("latitudeDifference"), field("lng").subtract(googleplex.longitude) .multiply(111 /* km per degree */) .pow(2) .alias("longitudeDifference") ) .select( field("latitudeDifference").add(field("longitudeDifference")).sqrt() // Inaccurate for large distances or close to poles .alias("approximateDistanceToGoogle") ) .execute()
Java
GeoPoint googleplex = new GeoPoint(37.4221, -122.0853); Task<Pipeline.Snapshot> result = db.pipeline() .collection("cities") .addFields( field("lat").subtract(googleplex.getLatitude()) .multiply(111 /* km per degree */) .pow(2) .alias("latitudeDifference"), field("lng").subtract(googleplex.getLongitude()) .multiply(111 /* km per degree */) .pow(2) .alias("longitudeDifference") ) .select( field("latitudeDifference").add(field("longitudeDifference")).sqrt() // Inaccurate for large distances or close to poles .alias("approximateDistanceToGoogle") ) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field googleplexLat = 37.4221 googleplexLng = -122.0853 result = ( client.pipeline() .collection("cities") .add_fields( Field.of("lat") .subtract(googleplexLat) .multiply(111) # km per degree .pow(2) .as_("latitudeDifference"), Field.of("lng") .subtract(googleplexLng) .multiply(111) # km per degree .pow(2) .as_("longitudeDifference"), ) .select( Field.of("latitudeDifference") .add(Field.of("longitudeDifference")) .sqrt() # Inaccurate for large distances or close to poles .as_("approximateDistanceToGoogle") ) .execute() )
EXP
構文:
exp(exponent: FLOAT64) -> FLOAT64
説明:
オイラー数を exponent でべき乗した値を返します(自然指数関数とも呼ばれます)。
例:
| 指数 | exp(exponent) |
|---|---|
| 0.0 | 1.0 |
| 10 | e^10(FLOAT64) |
+inf |
+inf |
-inf |
0 |
Web
const result = await execute(db.pipeline() .collection("books") .select(field("rating").exp().as("expRating")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("rating").exp().as("expRating")]) .execute()
Kotlin
val result = db.pipeline() .collection("books") .select(field("rating").exp().alias("expRating")) .execute()
Java
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(field("rating").exp().alias("expRating")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("rating").exp().as_("expRating")) .execute() )
LN
構文:
ln(number: FLOAT64) -> FLOAT64
説明:
number の自然対数を返します。この関数は、log(number) と同等です。
例:
| 数値 | ln(number) |
|---|---|
| 1 | 0.0 |
| 2L | 0.693... |
| 1.0 | 0.0 |
e(FLOAT64) |
1.0 |
-inf |
NaN |
+inf |
+inf |
x <= 0 |
[error] |
Web
const result = await execute(db.pipeline() .collection("books") .select(field("rating").ln().as("lnRating")) );
Swift
let result = try await db.pipeline() .collection("books") .select([Field("rating").ln().as("lnRating")]) .execute()
Kotlin
val result = db.pipeline() .collection("books") .select(field("rating").ln().alias("lnRating")) .execute()
Java
Task<Pipeline.Snapshot> result = db.pipeline() .collection("books") .select(field("rating").ln().alias("lnRating")) .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client.pipeline() .collection("books") .select(Field.of("rating").ln().as_("lnRating")) .execute() )
LOG
構文:
log(number: FLOAT64, base: FLOAT64) -> FLOAT64
log(number: FLOAT64) -> FLOAT64
説明:
base を底とする number の対数を返します。
numberのみが指定されている場合、baseを底とするnumberの対数を返します(ln(number)と同義)。
例:
| 数値 | 底 | log(number, base) |
|---|---|---|
| 100 | 10 | 2.0 |
-inf |
Numeric |
NaN |
Numeric. |
+inf |
NaN |
number <= 0 |
Numeric |
[error] |
Numeric |
base <= 0 |
[error] |
Numeric |
1.0 | [error] |
LOG10
構文:
log10(x: FLOAT64) -> FLOAT64
説明:
10 を底とする number の対数を返します。
例:
| 数値 | log10(number) |
|---|---|
| 100 | 2.0 |
-inf |
NaN |
+inf |
+inf |
x <= 0 |
[error] |
RAND
構文:
rand() -> FLOAT64
説明:
0.0(含む)と 1.0(含まない)の間で一様に選択された擬似乱数の浮動小数点数を返します。