Define Next Step using `Step2` in `__info()` Function

This guide explains how to define step2 inside a calculator metadata function (<name>__info()), so users can open a follow-up calculator with prefilled data.

What Step2 Does

step2 adds one or more Next Step buttons under calculation results. When a step is clicked, qCalc opens another calculator (or action) using data from the source calculator's latest run.

Typical uses:

Open another calculator with selected output values
Open a chart editor from an output chart
Open cost calculation (cost) from material quantities (e.g. brickwork, ccwork)
Open scenario analysis (scenario) from scenario comparison (compare)

Step2 Structure

Use a list of step objects in __info():

'step2': [
    {
        'step': 'run',
        'func': 'target_function_name',
        'caption': 'Button Label',
        'spec': {
            'target_arg_1': 'source_field_1',
            'target_arg_2': 'source_field_2',
        }
    }
]

Each item commonly uses:

step: action type (run or chart)
func: target calculator for run
caption: button text shown to user
spec: mapping/filter details

Step Type: run

Use step: 'run' to open another calculator and prefill inputs.

A. Direct field-to-argument mapping

'step2': [
    {
        'step': 'run',
        'func': 'bmr',
        'caption': 'Calculate BMR',
        'spec': {
            'weight': 'weight',
            'height': 'height',
        }
    }
]

Meaning:

target arg weight gets source value from field weight
target arg height gets source value from field height

B. Cost flow using run

'step2': [
    {
        'step': 'run',
        'func': 'cost',
        'caption': 'Calculate Cost of Materials',
        'spec': {
            'exclude': ['Brick Work Volume']
        }
    }
]

For func: 'cost', qCalc treats spec.include / spec.exclude as material-selection filters and prepares the cost calculator's items table automatically.

Supported patterns:

{'include': ['*'], 'exclude': ['Some Field']}
{'exclude': ['Some Field']}
standard mapping if you explicitly provide items mapping

Step Type: chart

Use step: 'chart' when output contains chart data and you want to open a chart function.

'step2': [
    {
        'step': 'chart',
        'caption': 'Modify Chart',
        'spec': {'field': 'Chart'}
    }
]

spec.field must match the output field name that contains chart data.

Multiple Step2 Buttons

You can add more than one step in order:

'step2': [
    {
        'step': 'run',
        'func': 'scenario',
        'caption': 'Open Scenario Postprocessor',
        'spec': {'scenarios': 'table'}
    },
    {
        'step': 'chart',
        'caption': 'Modify Chart',
        'spec': {'field': 'Chart'}
    }
]

Common Mistakes

Using step: 'run' without func
Using wrong output/source field names in spec
Expecting spec.include/spec.exclude to work for all target functions (they are meaningful for func: 'cost' flow)
Misspelling step2 key

Quick Checklist

Before saving a step2 config:

step2 is a list
each item has step and caption
run steps include func
spec field names match real input/output names
if target is cost, use run-style with func: 'cost'

Info Specify Next Step

Define Next Step using Step2 in __info() Function