The HP-35s was a revolutionary scientific calculator released by Hewlett-Packard, known for its algebraic entry system (similar to modern calculators) and its RPN (Reverse Polish Notation) capabilities (though this simulator focuses on common algebraic functions for simplicity). It offered a wide array of scientific and mathematical functions. This calculator aims to simulate some of the core mathematical operations found on the HP-35s.
Core Operations Simulated:
Addition (+): Sums two numbers. Equivalent to pressing + on the HP-35s after entering the second number.
Subtraction (-): Subtracts the second number from the first. Equivalent to pressing -.
Multiplication (*): Multiplies two numbers. Equivalent to pressing *.
Division (/): Divides the first number by the second. Equivalent to pressing /.
Power (x^y): Calculates the first number raised to the power of the second number (AB). Equivalent to pressing the y^x key.
Natural Logarithm (ln): Calculates the natural logarithm (base e) of a number. Equivalent to pressing the LN key. For this function, only 'Number A' is used.
Base-10 Logarithm (log): Calculates the common logarithm (base 10) of a number. Equivalent to pressing the LOG key. For this function, only 'Number A' is used.
e^x: Calculates 'e' raised to the power of the input number (eA). Equivalent to pressing the e^x key. For this function, only 'Number A' is used.
Square Root (sqrt): Calculates the square root of a number (√A). Equivalent to pressing the √x key. For this function, only 'Number A' is used.
While the HP-35s was a physical device, understanding its functions helps in performing complex calculations in various fields:
Engineering & Physics: Calculating powers, roots, logarithms, and exponential functions for formulas and equations.
Mathematics: Verifying results from calculus (logarithms, exponentials) and algebra (powers).
Science: Analyzing data that involves exponential growth/decay or logarithmic scales.
Education: Learning and practicing fundamental mathematical operations and scientific functions.
Example Usage:
To calculate 53:
Enter 5 in the 'Number A' field.
Select 'Power (x^y)' from the 'Operation' dropdown.
Enter 3 in the 'Number B' field.
Click 'Calculate'. The result should be 125.
To calculate the natural logarithm of 10:
Enter 10 in the 'Number A' field.
Select 'Natural Log (ln)' from the 'Operation' dropdown.
Leave 'Number B' empty or ensure it's not used by the selected function.
Click 'Calculate'. The result should be approximately 2.302585....
function calculateHP35s() {
var numA = parseFloat(document.getElementById("inputA").value);
var numB = parseFloat(document.getElementById("inputB").value);
var operation = document.getElementById("functionSelect").value;
var result = document.getElementById("calculationResult");
var calculatedValue = NaN; // Default to NaN
// Clear previous result styling
result.style.color = 'var(–primary-blue)';
result.style.backgroundColor = 'var(–result-bg)';
// Input validation for functions requiring two numbers
var requiresTwoNumbers = ['add', 'subtract', 'multiply', 'divide', 'power'];
if (requiresTwoNumbers.includes(operation)) {
if (isNaN(numA) || isNaN(numB)) {
result.textContent = "Error: Both numbers are required.";
result.style.color = 'red';
return;
}
}
// Input validation for functions requiring one number
var requiresOneNumber = ['log', 'log10', 'exp', 'sqrt'];
if (requiresOneNumber.includes(operation)) {
if (isNaN(numA)) {
result.textContent = "Error: Number A is required.";
result.style.color = 'red';
return;
}
}
// Perform calculations based on selected operation
switch (operation) {
case 'add':
calculatedValue = numA + numB;
break;
case 'subtract':
calculatedValue = numA – numB;
break;
case 'multiply':
calculatedValue = numA * numB;
break;
case 'divide':
if (numB === 0) {
result.textContent = "Error: Division by zero.";
result.style.color = 'red';
return;
}
calculatedValue = numA / numB;
break;
case 'power':
calculatedValue = Math.pow(numA, numB);
break;
case 'log':
if (numA 0 for ln.";
result.style.color = 'red';
return;
}
calculatedValue = Math.log(numA);
break;
case 'log10':
if (numA 0 for log10.";
result.style.color = 'red';
return;
}
calculatedValue = Math.log10(numA);
break;
case 'exp':
calculatedValue = Math.exp(numA);
break;
case 'sqrt':
if (numA = 0 for sqrt.";
result.style.color = 'red';
return;
}
calculatedValue = Math.sqrt(numA);
break;
default:
result.textContent = "Invalid operation selected.";
result.style.color = 'red';
return;
}
// Display the result
if (!isNaN(calculatedValue)) {
result.textContent = calculatedValue.toLocaleString(); // Format numbers nicely
} else {
// This case should ideally be caught by prior checks, but as a fallback:
result.textContent = "Calculation Error";
result.style.color = 'red';
}
}