注意: このページはまだ日本語に翻訳されていません。以下は英語の原文です。 
type FixedFormat: number | string | {
  "decimals": number;
  "signed": boolean;
  "width": number;
};
Returns a new FixedFormat for value. If value is specified as a number, the bit-width is 128 bits and value is used for the decimals. A string value may begin with fixed or ufixed for signed and unsigned respectfully. If no other properties are specified, the bit-width is 128-bits with 18 decimals. To specify the bit-width and demicals, append them separated by an "x" to the value. For example, ufixed128x18 describes an unsigned, 128-bit wide format with 18 decimals. If value is an other object, its properties for signed, width and decimals are checked.

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Source

utils/fixednumber.ts:52