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  • Quantum Basics
    • Overview
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    • Spatial Dimension
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    • Potential expression
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    • State Expression
    • Time Evolution
  • Operators
    • Overview
    • Hamiltonian Operator
    • Apply Operator To State
    • Position Operator
    • Linear Momentum Operator
    • Potential Operator
  • State Analysis
    • Overview
    • Overlap
    • Expectation Value
    • Squared expectation value
    • Standard Deviation
    • Variance
    • Fidelity
    • Integration
  • Linear Algebra
    • Overview
    • Spectrum
    • Get Eigenvalue
    • Linear Combination
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    • Scalar list
    • Scalar Expression
    • Get Real Part
    • Get Imaginary Part
  • Plots
    • Overview
    • Position Plot
    • Energy Plot
    • State Comparison Plot
    • Scalar time trace plot
    • Control comparison plot
    • State evolution plot
  • GPE Physics
  • Control
  • Misc.
    • Overview
    • Comment
    • For loop
    • State aggregation
    • Scope

Standard Deviation

Calculate the standard deviation $\sigma = \sqrt{\langle\hat{O}^2 \rangle - \langle\hat{O} \rangle ^2}$ of an operator $\hat{O}$.

Inputs

  • $\hat{O}$: Operator - the operator to calculate the standard deviation of
  • $\psi$: state - the state the system is in when we want the standard deviation.

Outputs

  • Scalar: real number - the calculated standard deviation.

Content

For convenience, the node displays its result directly.

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