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You added a table widget and gave it a reference ID (for example loads or beam_data). This guide shows how to use that table in other widgets—computed fields, checks, or any equation. Think of the table like a spreadsheet: rows, columns, and cells. In equations, the reference ID is the name of the whole block of numbers.
Start here: The reference ID is how you “call” the table from anywhere else. You usually do not use the raw matrix by itself—you pull one cell, one column, or an aggregate (max, min, sum) with the patterns below.

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Reference ID

How the table name is used in equations

One cell

Single value with matrixSubset

One column

Whole column, then max / min / sum

Vectors

Flat lists with vectorSubset

Inside the table

T(), rowIndex, and 0-based indices

Lookup widgets

L() instead of matrixSubset

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Reference ID

Every table widget has a reference ID you choose (or that comes from the template). That name is how you point at the table from anywhere else. Example: Your table’s reference ID is loads. In another widget’s equation, writing loads means: “use the entire table as one block of data.” You rarely want only that—you usually want one cell, one column, or a sum across rows. The next sections show how.

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One cell with matrixSubset

Use matrixSubset when you need a single value at a specific row and column.
  • Count rows and columns starting from 1 (first row = 1, first column = 1).
Pattern: 
matrixSubset(loads, rowNumber, columnNumber)
Example — first row, third column: 
matrixSubset(loads, 1, 3)
Example — inside a larger formula: 
abs(matrixSubset(loads, 1, 3))
That is the usual way to pull one cell from a normal table using its reference ID.
Full syntax and examples: Equation Functions (matrixSubset).

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One column with col

Sometimes every row has a value in the same column (for example “deflection” down the table). Use col to take that whole column, then wrap it in max, min, sum, etc.
  • Column numbers start at 1 for the leftmost column.
Pattern: 
max(col(loads, columnNumber))
Example — largest value in column 6: 
max(col(loads, 6))
If the table comes from a remote result and you need to wrap it (as in some templates), you might see matrix(...) around the reference—follow the same idea: pick the column number, then aggregate.
Details: Equation Functions (col()).

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Vectors with vectorSubset

If something is already a flat list of numbers (not a full table), use vectorSubset. Positions are counted from 1. Pattern: 
vectorSubset(someList, position)
Use this when the data is one row or one list, not a 2D table.

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Inside the same table

When the equation lives in a column of that same table (for example a computed column), you do not use the reference ID for “the cell to my left.” You use T, rowIndex, and colIndex.
  • T(row, column) refers to a cell in this table.
  • Inside the table, row and column indices start at 0 (first column = 0, first row = 0).
Examples:
  • Current row, first column: T(rowIndex(), 0)
  • Current row, second column: T(rowIndex(), 1)
Indexing: Outside the table, matrixSubset and col use 1-based row and column numbers. Inside the table, T() uses 0-based indices. Easy to mix up—pick the rule that matches where you are writing the equation.
More detail: Equation Functions (T()).

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Lookup widgets

Lookup and shared lookup widgets use L(referenceId, column), not matrixSubset. The column index for L starts at 0 for the left column. That is a different widget type than a normal editable table. See Lookup Widget and Equation Functions (L()).

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Cheat sheet

What you wantWhere you write itHow
One cell from your tableAnother widgetmatrixSubset(MyTable, row, col) — rows/cols from 1
Whole column, then e.g. maxAnother widgetmax(col(MyTable, col)) — col from 1
One item from a listAnother widgetvectorSubset(list, n) — n from 1
A cell in the same tableComputed column in that tableT(row, col) — from 0

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Optional: loops and growing tables

If the table can grow or shrink and you need to add up every row, templates often use setSum with size and matrixSubset. That is a more advanced pattern; the important part is still: your table’s reference ID is the handle, and matrixSubset / col are how you read from it.
Use this when you cannot hard-code row numbers and need to iterate over all rows (for example summing a column dynamically). Start from Equation Functions and existing templates that use setSum for a full pattern.

Table Widget

Configure tables, columns, and reference IDs

Equation Functions

matrixSubset, col, L, T, and more

Lookup Widget

When to use L() instead of a normal table

math.js background

Base math library used in equations