Resolve Odoo 12 error: “Unable to find Wkhtmltopdf on this system. The report will be shown in html”. Let’s see in this article how to solve.

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Let’s check which version is currently installed, with the following command:

wkhtmltopdf --version

if it is not installed, you will have:

Command 'wkhtmltopdf' not found, but can be installed with:
sudo apt install wkhtmltopdf

if it is installed verify that the version is 0.12.5. If the version is not correct give the command (this in Debian/Ubuntu system):

sudo apt-get remove --purge wkhtmltopdf

Let’s see how to install wkhtmltopdf:

wget ""\
"/download/0.12.5/wkhtmltox_0.12.5-1.bionic_amd64.deb" \
-O /tmp/wkhtml.deb

When we train a machine learning algorithm we have to be credible and prove that it is better than another model. In this article we will see the techniques to do this.

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How do I split the data of my set in order to make correct estimates of the performance of my ML algorithm? We will see it also with respect to the confidence limits. We will see how to evaluate two classifiers. Since in general there is no better technique than another, you have to compare the different approaches. Depending on the problem under examination, we have preferable approaches…

It will show you how to configure PyCharm to work with Python in a virtual environment. Also you will configure the requirements.txt.

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Start PyCharm create a new project or clone it from your repository. As an example I created a file to write inside the main. I specify that this is only an example and for reasons of brevity does not follow the structure of a Python project.

Install Python

First, make sure Python 3 is installed by running the following command:

python --version
python3 --version

If python 2 and 3 is installed, the output will be the installed version of…

We will deal with the representation of the data that are connatural with the techniques of data mining and machine learning. Many references are taken from the book DATA MINING — Practical Machine Learning Tools and Techniques.

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Data Mining

In order to understand what Data Mining is, we refer to concepts of data and information. A data is a value that belongs to a certain type and is typically stored in a database. From this data we want to extract an information, that is to associate a semantics to this data and from here extract in mining concept.

Mining represents the process…

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In una conferenza chiamata TED talks (Technology Entertainment Design), una serie di conferenze con cadenza annuale che parlano principalmente di tecnologia e design, Fei-Fei Li nel 2015 inizia il talk mostrando cosa è in grado di fare una bambina di tre anni, riconoscere immagini e descriverne il contenuto. Ma invita il pubblico a riflettere sul fatto che il più avanzato dei computer non è in grado di svolgere questo compito.
Fa notare che abbiamo fotocamere con milioni di megapixel, ma non abbiamo ancora ridato la vista ai ciechi. …

Control your Raspberry Pi from your PC, laptop, smartphone or tablet.

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Virtual Network Computing (or VNC) are software applications for remote access/control through graphical interface and used for the administration of your computer remotely. VNC is based on Remote Frame Buffer protocol (RFB). The RFB protocol is a client-server protocol and is described in detail in Request for Comments (RFC) 6143. The client is easy to implement and therefore can run on many different hardware.

The VNC server is installed on the computer to be controlled and receives commands from a VNC Viewer that sends various events such as header…

La pericolosa corsa degli esseri umani alla superiorità intellettuale.

Superiorità intellettuale

Nel carteggio “Perché la guerra?” pubblicato nel 1933, il fisico Einstein, affronta il tema della guerra con il fondatore della psicoanalisi Freud. Il fine è quello di analizzare il sentimento di odio e distruzione insito nell'uomo e trovare una soluzione al problema della pace nel mondo. Einstein scrive:

«Vi è una possibilità di dirigere l’evoluzione psichica degli uomini in modo che diventino capaci di resistere alla psicosi dell’odio e della distruzione?».

Nella lettera di risposta, inviata da Vienna nel settembre del 1932, Freud si occupa del rapporto tra diritto e forza…

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Functional testing requires the analysis of the outputs generated by the system (or its components) in response to input (test cases) defined on the basis of knowledge of the requirements of the system (or its components). Often made in Black Box mode, i.e. without access in any way to the internal structure of the software.

Functional testing is also called black box testing. We are interested in the contour of the system and have no information about what it looks like inside. Based on knowledge of the software structure, and in particular the code, associated inputs and oracle, for the…

Collection of all the Odoo errors, which I will find during the development, leading to the not nice Odoo Server Error or Frontend Errors.

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Odoo Internal Server Error

The operation cannot be completed

The operation cannot be completed:
- Create/update: a mandatory field is not set.
- Delete: another model requires the record being deleted. If possible, archive it instead.
Model: model name (, Field: String destription of field (field name)

In this case the Odoo model has a field, securely relational, named field name that refers to an Odoo model that you are about to delete.

No inverse field None found for ‘module name’

Odoo Server Error — Warning
No inverse field None found for ‘module name’

This happens when a One2many field has a bedside table that points to a model, in this example medium.story, that does not…

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Let’s start with a situation where we have a repository on Github where we want to develop our custom Odoo modules.

In the VCS menu, there is the item “Get from version control”

Gioacchino Lonardo

Computer Engineer, artificial intelligence enthusiast.

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