Calculator Inputs
Formula Used
For an m by n matrix A, singular values are found from the symmetric matrix ATA.
ATA v = λv
σi = √λi
The calculator computes ATA, estimates its eigenvalues with Jacobi rotations, and returns sorted square roots. It also reports rank, spectral norm, Frobenius norm, nuclear norm, stable rank, and condition number.
How to Use This Calculator
- Enter the number of rows and columns.
- Type each matrix row on a new line.
- Separate values with spaces, commas, or semicolons.
- Choose decimal places and a numerical tolerance.
- Press the calculate button to see results above the form.
- Use CSV or PDF export after a successful calculation.
Example Data Table
| Matrix | Rows | Columns | Expected Main Reading |
|---|---|---|---|
| 3 1 1 -1 3 1 |
2 | 3 | Two nonzero singular values show rank near two. |
| 1 0 0 1 |
2 | 2 | Both singular values equal one. |
| 2 4 1 2 |
2 | 2 | One tiny value shows dependent columns. |
Understanding Singular Values
Singular values describe the stretching strength of a matrix. They work for square and rectangular matrices. That makes them useful in many algebra tasks. A large singular value shows a direction with strong scaling. A small singular value shows weak scaling. A zero value shows lost dimension.
Why They Matter
These values help explain rank, stability, compression, and error growth. Engineers use them in signals and control work. Data teams use them in low rank models. Students use them to understand transformations. The largest singular value is the spectral norm. It measures the greatest possible stretch. The sum of all singular values is the nuclear norm. The square root of the squared sum gives the Frobenius norm.
How This Calculator Helps
This calculator builds A transpose A from your entries. It then finds the eigenvalues of that symmetric matrix. Singular values are the square roots of those eigenvalues. The tool sorts the values from largest to smallest. It also estimates rank using your tolerance. The condition number compares the largest value with the smallest reliable value. A high condition number can mean sensitive calculations.
Practical Reading Tips
Do not study one number alone. Compare the spread between values. A flat list means balanced scaling. A list with one dominant value suggests a main direction. Tiny values may be numerical noise. Adjust tolerance when entries are very large or very small. Use more decimals for classroom checking. Use fewer decimals for reports. CSV export supports spreadsheets. PDF export supports clean sharing. Always confirm entries before using results in assessed work.
Common Matrix Uses
Singular values appear in least squares, image compression, principal components, and numerical rank checks. They also reveal whether a matrix is close to losing information. For rectangular matrices, they give a clear size-independent summary. This makes the method stronger than determinant checks. Determinants only apply to square matrices. Singular values apply widely. They show geometry, stability, and structure in one ordered list.
For best accuracy, enter rows consistently. Avoid blank cells inside the matrix. Decimal and negative entries are accepted. Fractions should be converted first. When results seem unexpected, inspect the energy share column and retry with a smaller tolerance before drawing final conclusions.
FAQs
What is a singular value?
A singular value is a nonnegative number that measures matrix stretching along a special direction. Every matrix has singular values, even when it is not square.
Can I enter a rectangular matrix?
Yes. The calculator accepts rectangular matrices up to eight rows and eight columns. Singular values are especially useful for non-square matrices.
Why does the calculator use A transpose A?
The eigenvalues of A transpose A are nonnegative in exact arithmetic. Singular values are the square roots of those eigenvalues.
What does rank estimate mean?
The rank estimate counts singular values greater than the selected tolerance. Smaller tolerance values can classify more tiny values as nonzero.
What is the condition number?
It is the largest reliable singular value divided by the smallest reliable singular value. Large values suggest numerical sensitivity.
Why do I see a tiny zero-like value?
Floating point arithmetic can create very small values. Increase tolerance or reduce displayed decimals when the value is numerical noise.
Does this calculator show full decomposition?
This tool focuses on singular values and related diagnostics. It does not display full U and V matrices.
Can I export the result?
Yes. After calculation, use the CSV or PDF buttons. CSV suits spreadsheets, while PDF suits sharing and printing.