Calculate

Update values and re-evaluate a specific calculation in a CalcTree workspace

The Calculate mutation allows you to update and re-evaluate a specific calculation in a CalcTree workspace by providing input statements. It is used to perform a calculation based on provided input values. It takes a set of input statements, processes them, and returns the updated values for each statement in the calculation.

Input Parameters

Parameter	Type	Required	Description
workspaceId	ID!	Yes	The unique ID of the CalcTree workspace
calculationId	ID!	Yes	The unique ID of the calculation
revisionId	ID!	Yes	The unique ID of the revision to calculate
statements	[StatementInput!]!	Yes	An array of input statements for the calculation

Statements

‘Statements’ as used here refer to parameters, and code-sources on a page. A statement could be ; a parameter used to input a magnitude, a parameter with a formula that evaluates math, a Python code source with functions in it. Each statement has it's own unique statementID, which can be retrieved from the response from a getCalculation call.

Sample Mutation

query Calculate(
  $workspaceId: ID!,
  $calculationId: ID!,
  $revisionId: ID!,
  $statements: [StatementInput!]!
) {
  calculate(
    workspaceId: $workspaceId,
    calculationId: $calculationId,
    revisionId: $revisionId,
    statements: $statements
  ) {
    revisionId
    calculationId
    statements {
      statementId
      title
      formula
      namedValues {
        name
        value
      }
    errors
    }
  }
}

Named Values and pushing value updates to statements

Here, the namedValues array are in the response, and will return the resulting output of calculations. The fields in the namedValue array can not be updated. Rather, if values are to be updated, this is done by updating the value in the formula field. Example

If value of x is 3, and it is to be update to 5, to evaluate a calculation, the formula field needs to be updated from "formula": "x=3" to "formula": "x=5" .

Sample Header

{
  "x-api-key": "your_API_key" 
}

Sample Variables

{
  "workspaceId": "your-workspace-id",
  "calculationId": "your-calculation-id",
  "revisionId": "your-revision-id",
  "statements": [
    {
      "statementId": "oMByVYo8RukM1cRiZtQyK",
      "formula": "b = 300 mm"
    },
    {
      "statementId": "v7vYcy8NjM5vS2GKTdBA3",
      "formula": "h = 500 mm"
    },
    {
      "statementId": "Vdbfy9Qj6DzvMUM7Fe-QI",
      "formula": "F = 5000 N"
    },
    {
      "statementId": "NH0JQx2nnM9MGuoFvAwbJ",
      "formula": "A = 150 mm^2"
    }
  ]
}

If changing the value of the input b from 300mm to 500mm , then the array for that statement would need to be updated to:

{
  "statementId": "oMByVYo8RukM1cRiZtQyK",
  "formula": "b = 500 mm"
}

Note: the statementId must be maintained to update it's value.

Sample Response

{
  "data": {
    "calculate": {
      "revisionId": "rev5678",
      "calculationId": "your-calculation-id",
      "statements": [
        {
          "statementId": "oMByVYo8RukM1cRiZtQyK",
          "title": "Base Width",
          "formula": "b = 500 mm",
          "namedValues": [
            { "name": "b", "value": 500 }
          ],
          "errors": []
        },
        {
          "statementId": "v7vYcy8NjM5vS2GKTdBA3",
          "title": "Height",
          "formula": "h = 500 mm",
          "namedValues": [
            { "name": "h", "value": 500 }
          ],
          "errors": []
        },
        {
          "statementId": "Vdbfy9Qj6DzvMUM7Fe-QI",
          "title": "Force",
          "formula": "F = 5000 N",
          "namedValues": [
            { "name": "F", "value": 5000 }
          ],
          "errors": []
        },
        {
          "statementId": "NH0JQx2nnM9MGuoFvAwbJ",
          "title": "Area",
          "formula": "A = 150 mm^2",
          "namedValues": [
            { "name": "A", "value": 150 }
          ],
          "errors": []
        },
        {
          "statementId": "Di3lmw44HjOVV4Sfz3cJo",
          "title": "Moment of Inertia",
          "formula": "I = (b * h^3) / 12",
          "namedValues": [
            { "name": "I", "value": 520833333.33 }
          ],
          "errors": []
        },
        {
          "statementId": "C6RBN9BgyIjxfN04jOayT",
          "title": "Shear Stress",
          "formula": "V = F / A",
          "namedValues": [
            { "name": "V", "value": 33.33 }
          ],
          "errors": []
        }
      ]
    }
  }
}

Error field

The errors field appears in each statement of the calculate query response. It contains details if a formula fails to evaluate correctly.

Each error includes:

• A message describing the issue

• A _tag indicating the error type (e.g., "MathJSError")

• A cause block with structured data to help you debug the issue (e.g., what types were expected vs. received)

It’s recommended to always include the errors field in your query response to help diagnose any issues in the submitted formulas.

"errors": [
  {
    "cause": {
      "data": {
        "category": "wrongType",
        "fn": "addScalar",
        "index": 1,
        "actual": ["number"],
        "expected": ["Unit"]
      }
    },
    "_tag": "MathJSError",
    "message": "Error executing formula. 🐛"
  }
]

In this case, the formula attempted to add a unitless number (e.g. 100) to a value with units (e.g. 20m). The system expected a Unit, but received a number, causing a type mismatch.

Note: The errors field is intended to help diagnose issues in formula evaluation, but interpreting errors can sometimes be nuanced. While we aim to provide clear and structured error messages, debugging may still require some trial and error or best-effort interpretation in complex cases.

Description of Returned Fields

Field	Type	Description
revisionId	String	The unique ID of the new calculation revision
calculationId	String	The unique ID of the calculation
statements	Array	An array of the calculated statements
statementId	String	The unique ID of the statement
title	String	The title of the statement
formula	String	The formula used in the statement
namedValues	Array of Objects	An array of response name value pairs representing variables and their calculated values.
errors	Array of Objects	An optional array containing any errors that occurred during evaluation of the formula. Useful for debugging invalid formulas or type mismatches. Empty if no errors are present.

---

Usage Example in Python

Here’s how to use the Calculate mutation in Python using the requests library:

import requests

# Define the API endpoint and your API key
url = "https://graph.calctree.com/graphql"
headers = {
    "Content-Type": "application/json",
    "x-api-key": apiKey,
}

# Define the GraphQL query and variables
query = """
query Calculate($workspaceId: ID!, $calculationId: ID!, $revisionId: ID!, $statements: [StatementInput!]!) {
  calculate(workspaceId: $workspaceId, calculationId: $calculationId, revisionId: $revisionId, statements: $statements) {
    revisionId
    calculationId
    statements {
      statementId
      title
      formula
      namedValues {
        name
        value
      }
      errors
    }
  }
}
"""

variables = {
    "workspaceId": "your-workspace-id",
    "calculationId": "your-calculation-id",
    "revisionId": "your-revision-id",
    "statements": [
        {
            "statementId": "oMByVYo8RukM1cRiZtQyK",
            "formula": "b = 300 mm"
        },
        {
            "statementId": "v7vYcy8NjM5vS2GKTdBA3",
            "formula": "h = 500 mm"
        },
        {
            "statementId": "Vdbfy9Qj6DzvMUM7Fe-QI",
            "formula": "F = 5000 N"
        },
        {
            "statementId": "NH0JQx2nnM9MGuoFvAwbJ",
            "formula": "A = 150 mm^2"
        }
    ]
}

# Make the POST request
response = requests.post(url, json={"query": query, "variables": variables}, headers=headers)

# Print the response
print(response.json())

Tips for Using this query

• Ensure your workspaceId, calculationId, revisionId, and statements are accurate.

• Use the calculate query to extract the statement structure and statementIDs to use as inputs in this mutation.
• Unless working with a specific revision, set revisionID to "ffffffff" to access the latest version of the calculation.

• Use and update the formula field to change values.

• Keep statement IDs consistent when adjusting formulas.

• Use the namedValues array to understand the outputs of each statement.

• Include the error field in your reponse to help diagnose any issues in your query.