問20
頻出度★★☆
あるデータを表現するために, 1 個の JAN コードか 1 個の QR コードのどちらかの利用を検討する。表現できる最大のデータ量の大きい方を採用する場合, 検討結果として, 適切なものはどれか。
令和4年度 ITパスポート試験 問20
ストラテジ系法務 › 標準化関連
This question's explanation and your answers so far.
解説
問 20
Incorrectア
The JAN code can only represent 13 digits (8 digits in the shortened version), and its maximum data amount is far smaller than that of the QR code. Under the condition of adopting the larger one, it would not be chosen, so this is wrong.
- イ
正解 The JAN code is a one-dimensional (bar) code; even the standard type can only represent 13 digits, so the amount of information it can store is fixed and small. The QR code, by contrast, is a two-dimensional code that carries information in both the horizontal and vertical directions, and can represent a vastly larger amount of data — up to about 7,089 characters for numeric data, or about 4,296 characters for alphanumeric data. Under the condition of adopting whichever can represent the larger maximum amount of data, choosing the QR code is appropriate, so “イ” is correct.
Incorrectウ
Each code has a standard-defined maximum amount of data it can represent, and comparing those values settles which is larger. Saying that it cannot be decided because it varies with the content is wrong.
Incorrectエ
The maximum data amounts of the JAN code and the QR code are not the same; the QR code's is substantially larger. Saying that it cannot be decided because they are the same contradicts the facts and is wrong.
ここがポイント
- The JAN code is a one-dimensional code with a fixed number of digits (13 in the standard type), while the QR code is a two-dimensional code that can store thousands of characters; the QR code's maximum data amount is overwhelmingly larger.
- Grasp the difference in information capacity between one-dimensional and two-dimensional codes (a two-dimensional code carries information in both the horizontal and vertical directions, so its storage capacity is orders of magnitude larger).
用語