^([1-9][0-9]*)+(.[0-9]{1,2})?$
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===== Positive or Negative numbers with maximum 2 decimals =====
^(\-)?\d+(\.\d{1,2})?$
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===== Positive or Negative numbers and any decimal length =====
^(\-|\+)?\d+(\.\d+)?$
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===== Numbers with maximum 2 decimals =====
^[0-9]+(.[0-9]{2})?$
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===== Numbers with 1-5 decimals =====
^[0-9]+(.[0-9]{1,5})?$
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