Curve vs CSV Reader & Editor

'CurveFit' uses regression analysis by the method of least squares to find best fit for a set of data to a selected equation. The curve-fitting technique used in this app is based on regression analysis by the method of least squares. The free version fits a straight line through a data-set using least squares analysis. One In-App purchase is required to fit the other equations to the data set: Straight Line : Y = C0 + C1*X (free) Power Curve : Y = C0 + X^C1 Exponential I : Y = C0 * EXP(C1*X) Exponential II : Y = C0 * X * EXP(C1*X) Hyperbolic : Y = (C0 + C1*X)/(1 - C2*X) Square Root : Y = C0 + C1*SQRT(X) Polynomial : Y = C0 + C1*X + --- + CN*X^N Exponential Poly : Y = C0 * EXP(C1*X + --- + Natural Log : Y = C0 + C1*(LN(X)) + --- + Reciprocal : Y = C0 + C1/X + --- + CN/X^N Most literature deals with least squares analysis for straight lines, 2nd degree polynomials, and functions that can be linearized. The input-data is transformed into a format that the can be put into linear forms with undetermined constants. These types of equations are applicable for least-squares regression. The regression routine is needed for determining values for the set of unknown quantities C1, C2,- - - ,Cm in the equation: Y = C1 x F1(X) + C2 x F2(X) + - - - + Cm x Fm(X) The constants are determined to minimize the sum of squares of the differences between the measured values (Y1, Y2, - - - , Yn) and the predicted equation Yc = F(X) which is found by curve-fitting the given data. The principle of least squares is to find the values for the unknowns C1 through Cm that will minimize the sum of the squares of the residuals: n ∑(ri) = r12 + r22 + - - - + rn2 = minimum i=1 This is done by letting the derivative of the above equation equal zero. Thereby there will be generated as many algebraic equations as given data points, and the number of equations will be larger than unknowns.

Csv Editor - Smart Csv opens the CSV files other apps choke on. Files with hundreds of thousands of rows open in seconds, scroll smoothly, and edit like a real spreadsheet — right on your iPhone or iPad. EDIT LIKE A SPREADSHEET • Tap to select, tap again to edit — Excel-style on touch • Insert, delete, and reorder rows and columns • Undo and redo everything • Freeze rows and columns so headers stay put while you scroll • Select ranges with drag handles, clear whole ranges at once BUILT FOR BIG FILES • Opens 500,000+ row files without slowing down • Background loading with live progress — start reading immediately • Smooth flick-scrolling through the whole sheet SORT & FILTER • Excel-style AutoFilter per column • Sort text, numbers, and dates the way Excel does • Filtered rows are protected: edits and deletes never touch hidden data CHARTS (PRO) • Turn any selection into a chart in two taps • Bar, line, and more, powered by Swift Charts • Save chart images to your photo library or share them FORMULA COLUMNS (PRO) • Add a computed column that fills down every row, like a spreadsheet formula • Reference other columns by name — e.g. [Price] * [Qty] • Built-in functions: IF, ROUND, ABS, MIN, MAX, CONCAT, UPPER, LOWER, TRIM, LEN, CONTAINS • Live preview and inline error checking while you build the formula • Formulas save inside the CSV, so results are readable in any app SMART FORMAT HANDLING • Auto-detects delimiters, headers, and encodings • Opens TSV and other delimited files • Re-open with custom parse settings when a file is unusual FREE VS PRO The free version includes full editing, sorting, and filtering for files up to 100 rows. Csv Editor Pro unlocks: • Unlimited rows — open and edit files of any size • Charts • Formula columns Your files are never truncated: even in the free version, every row of your file is preserved when you save. Pro is available as a one-time lifetime purchase, or as a monthly or yearly auto-renewing subscription. Subscriptions renew unless canceled at least 24 hours before the end of the period and can be managed in your App Store account settings. Terms of Use: https://mygems.app/term Privacy Policy: https://mygems.app/privacy